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CHAPTER ONE: DEVELOPMENT OF THE Z1 900 SUPER FOUR. KAWASAKI HEAVY INDUSTRIES OR KHI FOR SHORT. NOT QUITE THE NAME YOU WOULD IMAGINE WHEN YOU THINK OF A MOTORCYCLE MANUFACTURER. NEVER THE LESS, KHI WAS FOUNDED ORIGINALLY IN 1878 BY SHOZO KAWASAKI, PRIMARILY AS A SHIPYARD, BUILDING OCEAN GOING STEEL SHIPS. IN 1886 THE OPERATION WAS EXPANDED TO BECOME THE KAWASAKI DOCKYARD, AND THEN TEN YEARS LATER ON, KAWASAKI STARTED EXPANDING INTO OTHER MODES OF CONSTRUCTION AND TRANSPORTATION. APART FROM BUILDING SHIPS, THEY BUILD HELICOPTERS, BRIDGES, TRAINS, ROBOTS AND AIRCRAFT, THEY EVEN BUILT THE MASSIVE BORING MACHINE THAT WAS USED FOR THE CHANNEL TUNNEL. THIS WAS INDEED A "HEAVY" IMAGE. THE KAWASAKI AIRCRAFT DEPARTMENT, WHICH WAS FORMED IN 1918, WAS RENAMED IN 1937 AS THE KAWASAKI AIRCRAFT COMPANY AND BECAME A LEADER IN AIRCRAFT DESIGN AND CONSTRUCTION. HOWEVER THE COMPANY FOUND ITSELF ON STICKY GROUND AFTER THE EFFECTS OF THE SECOND WORLD WAR. PRODUCING PLANES FOR "KAMIKAZES" WAS NOW CONSIDERED A "NO-NO"! THEREFORE, THEY HAD A LOT OF REDUNDANT RESOURCES AND MANPOWER TO HAND. THEY TURNED TO PRODUCING SMALL PETROL ENGINES AND WHEN THEY DECIDED TO LIGHTEN THEIR IMAGE THEY JUST WENT OUT AND BOUGHT A MOTORCYCLE MANUFACTURER. THE COMPANY IN QUESTION WAS THE MEGURO MANUFACTURING COMPANY. KAWASAKI HAD ALREADY PRODUCED MOTORCYCLE ENGINES IN CONJUNCTION WITH THE MEIHATSU COMPANY. AS EARLY AS 1954 THEY HAD PRODUCED A 58CC TWO STOKE ENGINE FOR MEIHATSU, BUT THEY HAD BIG PLANS FOR THE FUTURE AND MEIHATSU DID NOT FIGURE IN THEM. MEGURO WERE JAPANS OLDEST MOTORCYCLE COMPANY HAVING HAD PRODUCED BIKES FROM AS EARLY AS 1937, BUT THEY FOUND TRADE HARD GOING AFTER THE SECOND WORLD WAR AND THE DEAL WITH KAWASAKI SEEMED A CONVENIENT ONE. FOR KAWASAKI IT WAS PERFECT. MARKETING RIGHTS ALL OVER JAPAN AND SOUTH EAST ASIA FOR THE MEGURO OHV TWINS WAS THE PERFECT PLATFORM TO BUILD A DEALER NETWORK ON. BY 1961 THE PRODUCTION LINE IN KOBE WAS TURNING OUT THE FOUR STROKE TWINS OF MEGURO AND THEIR OWN BRANDED NAME TWO STROKE MOTORS. THEY NOW HAD A RANGE OF BIKES FROM 50CC TO 500 CC. THE STAGE WAS SET FOR THE QUICKEST RISE TO FAME OF ANY JAPANESE MOTORCYCLE MANUFACTURER. IN 1962 THE FIRST FULL MOTORCYCLE TO CARRY THE KAWASAKI NAME WAS PRODUCED. THIS WAS THE B8 MODEL, A 125CC TWO STROKE SINGLE. HOWEVER KAWASAKI DID NOT FORGET HOW IMPORTANT MEGURO WAS TO THEM AND CONTINUED TO USE THE MEGURO SYMBOL ON KAWASAKI MODELS UP TO THE EARLY SEVENTIES. THE SYMBOL IS STILL USED TODAY ON PACKAGING AND SIGNAGE. BY LATE 1966 KAWASAKI HAD A 650 TWIN FOUR STROKE ON SALE, THE W-SERIES. THIS WAS A DEVELOPMENT OF THE MEGURO TWIN AND BORE A REMARKABLE RESEMBLANCE TO THE BSA TWIN OF THE TIME, BUT WHILE IT WAS A SALES SUCCESS IN THEIR DOMESTIC MARKET, SALES IN THE IMPORTANT USA MARKET WAS POOR. AFTER ALL, WHY HAVE A COPY WHEN YOU CAN HAVE THE REAL THING. SOMETHING HAD TO BE DONE. THE OVERSEAS OFFICE IN CHICAGO USA, WAS FORMED IN 1965, READY AND WAITING TO FURTHER THE BRAND NAME ACROSS THIS VAST COUNTRY, BUT IN READINESS OF THE LAUNCH OF THE A1-MODEL 250 SAMURAI, KAWASAKI MOVED OFFICE TO LOS ANGELES AND IN MARCH OF 1966, AMERICA KAWASAKI MOTORS WAS ESTABLISHED. KAWASAKI CONTINUED DEVELOPING THEIR TWO STROKES IN JAPAN, INTRODUCING THE INFAMOUS TRIPLE RANGE BUT THEY KNEW A FOUR STROKE WAS NEEDED TO CAPTURE THE HEARTS OF THE ALL-IMPORTANT AMERICANS. THE W-SERIES RAN WELL INTO THE EARLY SEVENTIES, SUCH WAS THE DEMAND IN JAPAN, BUT KAWASAKI WANTED MORE. THEY WANTED

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Page 1: CHAPTER ONE: DEVELOPMENT OF THE Z1 900 SUPER FOUR..doc

CHAPTER ONE: DEVELOPMENT OF THE Z1 900 SUPER FOUR.

KAWASAKI HEAVY INDUSTRIES OR KHI FOR SHORT. NOT QUITE THE NAME YOU WOULD IMAGINE WHEN YOU THINK OF A MOTORCYCLE MANUFACTURER. NEVER THE LESS, KHI WAS FOUNDED ORIGINALLY IN 1878 BY SHOZO KAWASAKI, PRIMARILY AS A SHIPYARD, BUILDING OCEAN GOING STEEL SHIPS.IN 1886 THE OPERATION WAS EXPANDED TO BECOME THE KAWASAKI DOCKYARD, AND THEN TEN YEARS LATER ON, KAWASAKI STARTED EXPANDING INTO OTHER MODES OF CONSTRUCTION AND TRANSPORTATION.APART FROM BUILDING SHIPS, THEY BUILD HELICOPTERS, BRIDGES, TRAINS, ROBOTS AND AIRCRAFT, THEY EVEN BUILT THE MASSIVE BORING MACHINE THAT WAS USED FOR THE CHANNEL TUNNEL. THIS WAS INDEED A "HEAVY" IMAGE.THE KAWASAKI AIRCRAFT DEPARTMENT, WHICH WAS FORMED IN 1918, WAS RENAMED IN 1937 AS THE KAWASAKI AIRCRAFT COMPANY AND BECAME A LEADER IN AIRCRAFT DESIGN AND CONSTRUCTION. HOWEVER THE COMPANY FOUND ITSELF ON STICKY GROUND AFTER THE EFFECTS OF THE SECOND WORLD WAR. PRODUCING PLANES FOR "KAMIKAZES" WAS NOW CONSIDERED A "NO-NO"! THEREFORE, THEY HAD A LOT OF REDUNDANT RESOURCES AND MANPOWER TO HAND. THEY TURNED TO PRODUCING SMALL PETROL ENGINES AND WHEN THEY DECIDED TO LIGHTEN THEIR IMAGE THEY JUST WENT OUT AND BOUGHT A MOTORCYCLE MANUFACTURER. THE COMPANY IN QUESTION WAS THE MEGURO MANUFACTURING COMPANY.KAWASAKI HAD ALREADY PRODUCED MOTORCYCLE ENGINES IN CONJUNCTION WITH THE MEIHATSU COMPANY. AS EARLY AS 1954 THEY HAD PRODUCED A 58CC TWO STOKE ENGINE FOR MEIHATSU, BUT THEY HAD BIG PLANS FOR THE FUTURE AND MEIHATSU DID NOT FIGURE IN THEM. MEGURO WERE JAPANS OLDEST MOTORCYCLE COMPANY HAVING HAD PRODUCED BIKES FROM AS EARLY AS 1937, BUT THEY FOUND TRADE HARD GOING AFTER THE SECOND WORLD WAR AND THE DEAL WITH KAWASAKI SEEMED A CONVENIENT ONE. FOR KAWASAKI IT WAS PERFECT. MARKETING RIGHTS ALL OVER JAPAN AND SOUTH EAST ASIA FOR THE MEGURO OHV TWINS WAS THE PERFECT PLATFORM TO BUILD A DEALER NETWORK ON.BY 1961 THE PRODUCTION LINE IN KOBE WAS TURNING OUT THE FOUR STROKE TWINS OF MEGURO AND THEIR OWN BRANDED NAME TWO STROKE MOTORS. THEY NOW HAD A RANGE OF BIKES FROM 50CC TO 500 CC. THE STAGE WAS SET FOR THE QUICKEST RISE TO FAME OF ANY JAPANESE MOTORCYCLE MANUFACTURER.IN 1962 THE FIRST FULL MOTORCYCLE TO CARRY THE KAWASAKI NAME WAS PRODUCED. THIS WAS THE B8 MODEL, A 125CC TWO STROKE SINGLE. HOWEVER KAWASAKI DID NOT FORGET HOW IMPORTANT MEGURO WAS TO THEM AND CONTINUED TO USE THE MEGURO SYMBOL ON KAWASAKI MODELS UP TO THE EARLY SEVENTIES. THE SYMBOL IS STILL USED TODAY ON PACKAGING AND SIGNAGE.BY LATE 1966 KAWASAKI HAD A 650 TWIN FOUR STROKE ON SALE, THE W-SERIES. THIS WAS A DEVELOPMENT OF THE MEGURO TWIN AND BORE A REMARKABLE RESEMBLANCE TO THE BSA TWIN OF THE TIME, BUT WHILE IT WAS A SALES SUCCESS IN THEIR DOMESTIC MARKET, SALES IN THE IMPORTANT USA MARKET WAS POOR. AFTER ALL, WHY HAVE A COPY WHEN YOU CAN HAVE THE REAL THING. SOMETHING HAD TO BE DONE.THE OVERSEAS OFFICE IN CHICAGO USA, WAS FORMED IN 1965, READY AND WAITING TO FURTHER THE BRAND NAME ACROSS THIS VAST COUNTRY, BUT IN READINESS OF THE LAUNCH OF THE A1-MODEL 250 SAMURAI, KAWASAKI MOVED OFFICE TO LOS ANGELES AND IN MARCH OF 1966, AMERICA KAWASAKI MOTORS WAS ESTABLISHED.KAWASAKI CONTINUED DEVELOPING THEIR TWO STROKES IN JAPAN, INTRODUCING THE INFAMOUS TRIPLE RANGE BUT THEY KNEW A FOUR STROKE WAS NEEDED TO CAPTURE THE HEARTS OF THE ALL-IMPORTANT AMERICANS. THE W-SERIES RAN WELL INTO THE EARLY SEVENTIES, SUCH WAS THE DEMAND IN JAPAN, BUT KAWASAKI WANTED MORE. THEY WANTED TO BUILD THE BEST MOTORCYCLE IN THE WORLD. IN ADDITION, THEY WANTED THE AMERICANS TO LOVE IT.IN 1967 A PROJECT TEAM WAS FORMED AND A THOROUGH INVESTIGATION INTO THE USA MARKET WAS STARTED. THE TEAM BACK IN JAPAN UNDER THE GUIDANCE OF GYOICHI "BEN" INAMURA WAS GIVEN A BRIEF OF WHAT WAS EXPECTED OF THEM.A FOUR STOKE, FOUR CYLINDER SPORTS TOURER WITH A LARGE DISPLACEMENT ENGINE OF A TYPE NEVER SEEN BEFORE IN JAPAN.THE CODENAME FOR THIS MACHINE WOULD BE N600. EVENTUALLY THE TEAM PRODUCED A WOODEN MOCK UP OF A 750CC DOUBLE OVERHEAD CAMSHAFT FOUR AND IN SEPTEMBER 1968 PRESENTED IT TO THE BOARD. THIS WAS GIVEN THE THUMBS UP AND MASS PRODUCTION WAS

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SET FOR 1969.WORK CONTINUED AND TESTING WAS CARRIED OUT IN JAPAN AND THE USA. ALL WAS GOING TO PLAN.THEN DISASTER. UNKNOWN TO KAWASAKI, HONDA HAD BEEN WORKING ON A SIMILAR PROJECT. THE CB750 FOUR WAS UNVEILED AT THE 1968 TOKYO SHOW. ALMOST IDENTICAL TO THEIR OWN CONCEPT, THIS BIKE TOOK THE WORLD BY STORM.IT WAS A BITTER PAINFUL BLOW TO KAWASAKI AND THE TEAM HAD NO OPTION BUT TO RETURN TO THE DRAWING BOARD.THEY LOOKED CAREFULLY AT THE CB750 IN DETAIL. THEY OBSERVED THE REACTION TO THIS BIKE IN THE WORLD MARKET AND DECIDED TO GO AHEAD WITH THEIR PROJECT. RENAMED PROJECT T103 AND ARMED WITH MOUNTAINS OF DATA AND TEST REPORTS THEY SLOWLY MADE THEIR PLANS.BACK TO AMERICA IN 1969 TO EVALUATE THE MARKET YET AGAIN. COULD THEY BUILD A BIGGER BIKE? UNDER THE USA CODENAME "NEW YORK STEAK" THEY CONTINUED DEVELOPMENT, TRYING ENGINES BETWEEN 900CC AND 1200CC.A 900CC ENGINE WAS CONSIDERED TO BE THE OPTIMUM SIZE AND BY THE SPRING OF 1970 THE FIRST PROTOTYPE WAS READY FOR TESTING AT THE YATABE TEST COURSE NEAR TOKYO.95 BHP AND A TOP SPEED OF OVER 140 MPH WAS OBTAINED BY ONE OF THE BIKES, WHILE ANOTHER BIKE DISGUISED AS A CB750 WAS DRIVEN MANY MILES IN AN EFFORT TO GAUGE HANDLING AND RELIABILITY. BY SEPTEMBER OF 1971, FINAL TESTS HAD BEEN COMPLETED AND IT WAS LEFT TO MR. T YAMADA, GENERAL MANAGER OF KAWASAKI'S MOTORCYCLE DIVISION, TO FINALLY GIVE THE ORDERS TO BEGIN PRODUCTION.KAWASAKI WERE HAPPY. THE FIRST PRE-PRODUCTION MODELS WERE AVAILABLE FOR SHAKE DOWN TESTS IN FEBRUARY 1972 AND MASS PRODUCTION BEGAN IN MAY 1972. THE NEW BIKE, THE 900 SUPER FOUR MODEL Z1, AS IT WAS TO BE KNOWN, WAS SHOWN TO THE MOTORCYCLE PRESS, FROM ALL OVER THE WORLD, AT A SPECIAL MEETING ON SEPTEMBER 16 1972 AT THE IFMA MOTORCYCLE SHOW IN COLOGNE.THE RESPONSE WAS AMAZING. "BETTER THAN THE HONDA CB750" WAS THE OPINION OF EVERYBODY WHO SAW OR WAS LUCKY ENOUGH TO RIDE IT. THE BIKE WAS RIGHT, THE PRICE WAS RIGHT, AND THE TIME WAS RIGHT. THE KING WAS DEAD, LONG LIVE THE KING.THE Z1, PEOPLE WERE NOW FED UP WITH CALLING IT THE 900 SUPER FOUR-MODEL Z1, WENT ON TOUR. AFTER THE DEBUT AT THE COLOGNE SHOW IT WENT ON TO PARIS THEN OSLO AND IN NOVEMBER, THE EARLS COURT SHOW IN LONDON.THE MOTORCYCLE PRESS IN THE UK WAS DIVIDED. THE AILING BRITISH BIKE INDUSTRY WAS STILL SMARTING FROM THE ONSLAUGHT OF PREVIOUS JAP BIKES AND THIS MUST HAVE SEEMED LIKE THE FINAL NAIL IN THE COFFIN. IT WAS NOT CHEAP AT £1088 BUT IT WAS A LOT OF MOTORCYCLE FOR YOUR MONEY. IT OFFERED THE AVERAGE MAN IN THE STREET THE ULTIMATE MOTORCYCLE AT AN AFFORDABLE PRICE. THE MEN AT KAWASAKI HAD DONE VERY WELL INDEED. THOSE WITH RESERVE WERE SOON CONVERTED BY THE CHARM OF THE Z1. MOVIE STARS, POP STARS, THE RICH AND THE FAMOUS ALL PRAISED THE BIKE AND THE ORDER BOOKS WERE SOON FULL TO BURSTING."TO HEAVY", "TO COMPLICATED," "TO THIRSTY," "YOU CAN'T FIX IT AT THE SIDE OF THE ROAD." THE CYNICS WERE SOON SILENCED. KAWASAKI HAD NOT SPENT 5 YEARS JUST PLAYING WITH WOODEN AND CLAY MODELS. THEY KNEW HOW TO MAKE AN ENGINE. THEY MADE THIS ENGINE MUCH TO STRONG FOR THE PURPOSE IT WAS INTENDED FOR. NO ONE WOULD BREAK THIS MOTOR. IT WAS "BULLET PROOF". SO STARTED THE LEGEND. THE Z1 "KING OF THE ROAD". THE FINAL SPECIFICATION FOR THE Z1 WAS 903CC, 82 BHP @ 8.500 RPM WITH MAXIMUM TORQUE AT 7.000 RPM. THE MODEST 8.5:1 COMPRESSION RATIO ENSURED THE USE OF UNLEADED PETROL WHICH WAS VERY IMPORTANT TO THE US MARKET. INDEED THE WHOLE ENGINE WAS DESIGNED WITH ANTI-POLLUTION IN MIND. KAWASAKI FORESAW THIS AS AN IMPORTANT SELLING POINT TO THE ENVIRONMENTALLY FRIENDLY AMERICANS. KAWASAKI CLAIMED A REDUCTION OF 40% IN HYDROCARBONS, DUE TO THE USE OF A POSITIVE CRANKCASE VENTILATION SYSTEM AND A LOW NOISE LEVEL OF 83DB. ALL THIS WAS VERY WELL AND GOOD, BUT AT THE END OF THE DAY THIS BIKE HAD WHAT REALLY MATTERED, PERFORMANCE WITH A CAPITAL "P". THE Z1 WAS NOT JUST A BIKE; IT WAS A STATEMENT, A WAY OF LIFE.NEVER THE LESS, KAWASAKI WENT TO GREAT PAINS TO POINT OUT THAT THE Z1 WAS FOR THE EXPERIENCED RIDER AND SHOULD BE TREATED WITH RESPECT.WITHIN MONTHS THE Z1 WAS BEING USED ON RACETRACKS ALL OVER THE WORLD. ENDURANCE RECORDS WERE BEING BROKEN, QUARTER MILES TIMES WERE BROKEN AND STILL THE MIGHTY

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Z1 COULD THEN BE RIDDEN HOME AND BACK TO WORK AGAIN ON MONDAY MORNING. THE POWER AND THE GLORY OF A RACE BIKE WAS NOW AVAILABLE TO ANYONE AND EVERYONE.INTERNATIONAL ACCLAIM WAS BESTOWED UPON THE Z1 IN EVERY COUNTRY. IN ENGLAND IT BROKE THE NORTON COMMANDO FIVE-YEAR STRANGLEHOLD IN THE "MOTOR CYCLE OF THE YEAR" AWARD AND WAS THE FASTEST BIKE THAT "MOTOR CYCLE NEWS" HAD TESTED.IN EARLY 1973, THREE Z1`S WERE TAKEN TO DAYTONA RACE CIRCUIT IN THE USA AND BROKE EVERY RECORD IN THE BOOK. IN 24 HOURS THE Z1 WENT THE FURTHEST, THE FASTEST AND THE QUICKEST. THE FIRST TRUE "SUPERBIKE" WAS BORN.BACK HOME IN THE UK, THE ONLY FLY IN THE OINTMENT WAS THE RELATIVE POOR PARTS BACKUP AND A RELUCTANCE OF SOME INSURANCE COMPANIES TO COVER IT. THE BAD CLAIMS RECORDS BETWEEN THE KAWASAKI TRIPLE RANGE AND INSURANCE COMPANIES IN THE UK WERE STILL STRONG IN THE MINDS OF SOME PEOPLE AND MANY WERE WARY OF THIS NEW EXOTIC EXPENSIVE MOTORCYCLE.KAWASAKI UK DID NOT EXIST YET AND THE AGRATI COMPANY OF NOTTINGHAM HANDLED ALL SALES. THE SALES BACKUP LEFT SOMETHING TO BE DESIRED IN THOSE DAYS AND MANY DEALERS FOUND THE 6 MONTHS WARRANTY TO BE SOMEWHAT OF A HEADACHE. SOME DEALERS EVEN HAD TO FLY OUT TO THE KAWASAKI PARTS WAREHOUSE IN HOLLAND AND BRING BACK THE SPARES THEMSELVES. IT MUST OF BEEN WORTH IT THOUGH BECAUSE MANY DEALERS PROSPERED ON THE STRENGTH OF THE Z-RANGE AND WENT ON TO BECOME SOME OF THE BIGGEST NAMES IN THE BUSINESS.NO RECORDS EXIST FROM 1973 BUT IT IS BELIEVED THAT LESS THAN 60 OF THE ORIGINAL Z1 MODELS CAME TO THE UK. MASSIVE INCREASE IN IMPORTS RECENTLY HAVE PUSHED THAT FIGURE UP CONSIDERABLY. WHAT WAS ONCE A VERY RARE BIKE IS NOW ALMOST COMMONPLACE AT A CLASSIC BIKE MEETING. PERHAPS A SHAME BUT THIS MUST SURELY REFLECT THE GREAT INTEREST IN THIS TRUE CLASSIC SUPERBIKE.AN ORIGINAL Z1 IS A STRANGE BEAST. DEPENDING ON WHICH BROCHURE OR PHOTOGRAPH YOU LOOK AT WILL RESULT IN MANY DIFFERENT PERMUTATIONS ON WHAT EXACTLY IS STANDARD. FOR THE PURPOSE OF THIS BOOK I WILL BE CONCENTRATING ON BOTH THE UK AND USA SPECIFICATION.THIS TRULY INTERNATIONAL BIKE DIFFERED IN NEARLY EVERY COUNTRY IT WAS SOLD IN. LOCAL LAWS AND REGULATIONS COVERING LIGHTS, INSTRUMENTS AND FENDERS INSURED MANY DIFFERENCES.THE OFFICIAL PARTS BOOK ISSUED BY KAWASAKI WAS EVEN INCORRECT. THE DIFFERENCE IN TIME BETWEEN PRINTING AND THE LAUNCH OF THE MODEL RESULTED IN SOME OF THE PARTS BEING SUPERSEDED BEFORE THE BIKE EVEN HIT THE SHOWROOM. WHERE POSSIBLE I WILL POINT THESE OUT AND TRY TO EXPLAIN THE REASON FOR THE MODIFICATION.I WILL BE COVERING ALL THE 900 MODELS UP TO 1976 INCLUDING THE Z1, Z1-A, Z1-B, Z900-A4, KZ900-A4 AND THE KZ900-B1 (USA LTD VERSION). I WILL ALSO BE MENTIONING THE JAPANESE DOMESTIC MODELS, THE Z2. THIS WAS THE 750 VERSION THAT NEARLY WAS THE BIKE THAT WE WERE SUPPOSED TO GET IF IT WAS NOT FOR THE LAUNCH OF THE HONDA CB750. THANK YOU VERY MUCH MR. HONDA!

MY FIRST EXPERIENCE WITH THE Z1 WAS IN 1975. AFTER MISSING THE BUS LATE ONE NIGHT AFTER A T-REX CONCERT IN MANCHESTER TOWN CENTRE, WE DECIDED TO WALK HOME. THE ROUTE TOOK US PAST THE LOCAL HARLEY DAVIDSON DEALER IN THE KNOTT MILL AREA OF MANCHESTER.THE SAME DEALER, KNOTT MILL MOTORCYCLES, HAD ALSO BEEN SELLING COSSACK MOTORCYCLES AND NOW THE KAWASAKI RANGE. WE STOPPED TO LOOK INTO THE WINDOWS AS ALL 15 YEAR OLD KIDS DID AND THEY'RE IN BETWEEN A COSSACK AND A HARLEY DAVIDSON ELECTRA-GLIDE, STANDING MAJESTICALLY WAS THE Z1. I STOOD THERE FOR 20 MINUTES STARRING AT THIS BROWN AND ORANGE SUPERBIKE. IT WAS LIKE A ROSE BETWEEN TWO THORNS. I MADE MY MIND UP THERE AND THEN; THIS WAS THE BIKE FOR ME.ONLY 2 YEARS, EXAM RESULTS, A JOB AND A WHOLE LOT OF MONEY STOOD BETWEEN ME AND THIS PIECE OF AUTOMOTIVE ART. THOSE TWO YEARS PASSED VERY QUICKLY, BUT THE EXUBERANCE OF YOUTH ENSURED THAT I WAS TO LOWER MY SIGHTS FINANCIALLY AND I ENDED UP WITH, OF ALL THINGS, ON MY SEVENTEENTH BIRTHDAY, A NEW 1975 MODEL CB250-G5 HONDA! TWO YEARS LATER I WAS AGAIN BACK AT KNOTT MILL KAWASAKI PRESSING MY FACE UP AGAINST THE WINDOW, THIS TIME CASH IN HAND. BIG PROBLEM! THE Z1 WAS NOW A Z1000. UNDETERRED I PARTED WITH MY MONEY AND RODE HOME ON A NEW Z1000-A1.

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UNBELIEVABLY, THE Z1000 PROVED TO BE A BIT UNRELIABLE AND I BECAME A REGULAR VISITOR TO KNOTT MILL OVER THE NEXT FEW MONTHS. THE BOSS THERE, ARTHUR ARNOLD, JOKED THAT HE WOULD HAVE TO FIND ME A JOB IF I BECAME ANY MORE REGULAR. ONE BUSY SATURDAY I TOOK UP HIS OFFER AND SO BEGAN A LASTING RELATIONSHIP WITH KAWASAKI THAT SAW ME IN 1978 GIVING UP MY JOB AS A PHARMACIST, TO WORK AT THE SAME SAID SHOP AS STORES MANAGER. SUCH WAS THE ATTRACTION OF THE "Z" THAT I WOULD HAVE WILLINGLY WORKED FOR NOTHING JUST TO BE SURROUNDED BY THESE MIGHTY KAWASAKI'S. I BEGAN RESTORING EARLY KAWASAKI MODELS AND RESTORED MY FIRST Z1 IN 1979 IN READINESS FOR THE "BELLE VUE" MOTORCYCLE SHOW IN MANCHESTER.I LEFT KNOTT MILL IN 1984 TO TAKE ON A NEW CHALLENGE, MANAGER OF HUDDERSFIELD KAWASAKI IN YORKSHIRE. THREE YEARS LATER I STARTED THE Z-POWER COMPANY, SUPPLYING PARTS AND RESTORING THE Z-RANGE. I NOW SPEND ALL MY DAYS WITH A Z1 NEVER MORE THAN AN ARMS REACH AWAY. I HAVE BEEN VERY FORTUNATE AND THERE IS NOTHING ELSE IN THE WORLD I WOULD RATHER BE DOING.

DAVE MARSDENDECEMBER 1998

CHAPTER TWO: THE ORIGINAL Z1. STARTING FRAME NO: Z1F-000001-Z1F-020000 THE ROLLING CHASSIS.

THE ORIGINAL Z1. JUST WHAT IS AN ORIGINAL Z1? WELL, DEPENDING ON WHICH COUNTRY YOU LIVE IN, IT WILL BE EITHER A 1972 OR 1973 903CC 4-CYLINDER 4-STROKE AIR COOLED SUPERBIKE. AN ORIGINAL Z1, AS STOOD IN THAT SHOWROOM IN 1973, WOULD NOT HAVE WON ANY "CONCOURS" COMPETITION. THE FINISH OF THIS FLAGSHIP WAS ACCEPTABLE FOR THE TIME BUT IT WOULD NOT COMPETE WITH THE MORE MODERN "RETRO`S. WE MUST REMEMBER THAT THIS BIKE WAS DESIGNED IN THE SIXTIES AND BUILT IN THE EARLY SEVENTIES WITH WHAT MATERIALS WERE AVAILABLE AT THE TIME. MOST RECENT RESTORATIONS ARE FAR SUPERIOR TO THE ORIGINAL SPECIFICATION BUT THIS IS TRUE IN MOST AUTO-RESTORATIONS. IF NOTHING ELSE, THE QUALITY OF GENUINE REPLACEMENT PARTS HAVE IMPROVED, AS WELL AS IMPROVEMENTS IN PAINTING AND METAL FINISHING.

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THE TERM "ROSE TINTED SPECTACLES" IS OFTEN OVERUSED BUT IT IS QUITE TRUE IN THIS CASE.

1972/1973 Z1-900 SUPER FOUR.

FRAME:THE FRAME ON THE Z1 WAS A STEEL DUPLEX CRADLE TYPE UNIT; SIMILAR TO THE FRAME USED ON THE TRIPLE RANGE. THE FINISH OF THE WELDS ON THE VARIOUS ATTACHED BRACKETS WAS OFTEN DESCRIBED AS "SPLATTER WELD", OR SOMETIMES EVEN WORSE! THIS WAS NORMAL FOR THE TIME AND IF NOTHING ELSE, IT WAS MORE THAN ADEQUATE. NOBODY COMPLAINED OF ANYTHING FALLING OFF, SO IT WAS A CASE OF FUNCTION OVER BEAUTY. THE FRAME WAS PAINTED IN A GLOSS BLACK FINISH. NO PRIMER OR LACQUER WAS EVIDENT, AND THE THICKNESS OF THE PAINT VARIED BETWEEN BIKES. I HAVE SEEN FRAMES STILL WITH A THICK COAT OF PAINT AFTER 25 YEARS BUT THEN AGAIN I HAVE SEEN RUST SETTING IN AFTER 12 MONTHS. THERE ARE MANY DIFFERENT WAYS OF RE-PAINTING THE FRAMES THESE DAYS, INCLUDING PLASTIC COATING, BUT I HAVE FOUND THE MOST ORIGINAL FINISH TO BE BY RUBBING DOWN TO BARE METAL AND THEN THREE COATS OF PRIMER FOLLOWED BY SIX COATS OF GLOSS BLACK ENAMEL SPRAY PAINT. CELLULOSE PAINT WILL WORK BUT IT WILL FADE WITH TIME. HOWEVER, MOST PEOPLE WILL NOT BE BOTHERED OR ABLE TO DO THIS AND USE AN EPOXY COATING COMPANY TO CARRY OUT THE WORK. THERE ARE MANY COMPANIES SPECIALISING IN FRAME COATINGS AND THEY DO AN EXCELLENT AND COST EFFECTIVE JOB.UNDERNEATH THE HEADSTOCK WAS A TRIANGULAR PLATE, WHICH ACTED AS BOTH A STRENGTHENING POINT AND AS A MOUNTING POINT FOR THE OPTIONAL EXTRA OIL COOLER KIT. IT SOON BECAME APPARENT THAT SMALL CRACKS WERE FORMING IN THIS PLATE, EVEN WITHOUT THE OIL COOLER FITTED. KAWASAKI BROUGHT OUT A "FRAME STRENGTHENING KIT" WHO CONSISTED OF A SMALL STRIP OF METAL, WHICH MOUNTED BETWEEN THE OIL COOLER MOUNTINGS AND BASICALLY, DID NOTHING! THE PART NUMBER OF THIS KIT WAS 99990-532. THEY LATER MODIFIED THE FRAME AND CHANGED THE PART NUMBER. ALL NEW FRAMES WOULD HAVE THE MODIFIED SECTION ON THEM. THE PART NUMBER FOR THE OLD FRAME WAS 32002-055 WHILE THE NEW NUMBER WAS 32002-1018.THE CHASSIS NUMBER WAS STAMPED ON THE HEADSTOCK. THE IDENTIFICATION ALWAYS BEGAN WITH Z1F AND THEN THE NUMBER. THE "F" WAS FOR FRAME. AMERICAN MODELS ALSO HAD A WHITE OBLONG STICKER STATING THE MONTH AND YEAR OF MANUFACTURE AS WELL AS THE FRAME NUMBER. THIS WAS NOT THE DATE OF REGISTRATION AND IT CAN CAUSE CONFUSION WHEN TRYING TO REGISTER AN AMERICAN IMPORT. ON THE PLUS SIDE, IT CAN PROVE THE DATE OF MANUFACTURE TO ASSIST OWNERS IN OBTAINING PRE 1973 ROAD FUND LICENSE EXCLUSION.THE ONLY OTHER PROBLEM WITH FRAMES WERE ACCIDENT DAMAGE AND THE STRANGE HABIT OF PREVIOUS OWNERS REMOVING CERTAIN BRACKETS TO SAVE WEIGHT. REAR FOOTREST AND EXHAUSTS MOUNTINGS WERE USUALLY THE FIRST TO GO FOLLOWED BY THE SIDE AND MAIN STAND BRACKETS. THE RIGHT HAND FRONT OF THE FRAME ALSO HAD A BRACKET TO WHICH YOU COULD ATTACH A STEERING DAMPER, BUT THIS IS OFTEN BROKEN OFF. CHECK ALL THE BRACKETS BEFORE YOU SPEND TIME AND MONEY REPAINTING THE FRAME.

FRONT SUSPENSION:THE FRONT FORKS WERE HYDRAULICALLY DAMPED TELESCOPIC WITH HARD CHROMED INNER STANCHIONS AND LIGHT ALLOY BOTTOM OUTERS. THERE WAS A BOSS ON THE OUTSIDE OF THE LOWERS WHERE A REFLECTOR WAS ATTACHED ON AMERICAN MODELS, WHILE THE UK HAD A CHROME DISC FITTED INSTEAD.THE FORK TUBES WERE 36MM IN DIAMETER AND WERE SEALED WITH AN OIL SEAL AND PROTECTED BY A RUBBER DUST COVER. A DAMPING PISTON CONNECTED THE INNER AND LOWER FORKS TOGETHER AND WAS SECURED AT THE BOTTOM OF THE FORK BY AN ALLEN SCREW. A SPECIAL TOOL WAS REQUIRED TO SEPARATE THE PARTS BUT MOST OWNERS IMPROVISED WITH WHAT TOOLS THEY POSSESSED. 170CC OF FORK OIL WAS REQUIRED FOR EACH FORK LEG.

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EACH LOWER LEG HAD TWO MOUNTING POINTS FOR THE BRAKE CALLIPERS, ALTHOUGH ONLY THE LEFT ONE WAS USED AS STANDARD. TWO 8MM STUDS WERE SCREWED INTO THE BOTTOM OF EACH OF THE LOWER LEGS WHICH SECURED THE AXLE CLAMPS BY USING 8MM NUTS AND SPRING WASHERS.THE FORK SPRINGS WENT INSIDE EACH STANCHION AND WERE SECURED AT THE TOP BY A LARGE ALUMINIUM NUT AND O`RING.THE BOTTOM FORK LEGS WERE POLISHED AND THEN LACQUERED, BUT NOT TO A MIRROR FINISH, MORE A "BRUSHED" EFFECT. TYPICAL OF THE JAPANESE AT THIS TIME, THE BACK OF THE FORK LOWERS WERE NOT POLISHED AT ALL AND WERE LEFT IN THEIR NATURAL STATE. THERE WAS NO POINT POLISHING WERE YOU COULD NOT SEE!THE BOTTOM YOKE WAS FINISHED IN GLOSS BLACK. TWO CHROMED 12MM BOLTS CLAMPED THE FORKS INTO THE YOKE. THE STEERING LOCK ALSO FASTENED TO THE YOKE. THERE WERE VARIOUS DIFFERENT LOCKS DEPENDING ON THE MARKET IT WAS INTENDED FOR. THERE WAS AN 8MM HOLE DRILLED THROUGH THE RIGHT HAND SIDE OF THE YOKE FOR OWNERS TO FIT THE 7 WAY OIL DAMPED STEERING DAMPER FROM THE TRIPLE RANGE.THE TOPE YOKE WAS FINISHED IN A SATIN BLACK FINISH. KAWASAKI CALLED THIS FINISH "FLAT BLACK". THREE CHROME 8MM BOLTS CLAMPED THE FORKS WHILE A LARGE CHROME NUT AND WASHER FASTENED THE YOKES TOGETHER. THE YOKES WERE ATTACHED TO THE FRAME USING FOUR BALL RACES AND CONES. 39 BALL BEARINGS WERE USED, 20 AT THE BOTTOM AND 19 AT THE TOP. TAPER ROLLER BEARINGS ARE NOW AVAILABLE AS AN AFTER-MARKET OPTION. A LARGE CASTLE TYPE NUT THAT SCREWED ONTO THE BOTTOM YOKE STEM ADJUSTED THE HEADRACES.BETWEEN THE TWO YOKES, SLIDING ON THE FORK STANCHIONS WERE TWO CHROME HEADLAMP BRACKETS WHICH ALSO HELD THE FRONT INDICATOR STEMS. THESE WERE CUSHIONED BY A COLLECTION OF DAMPER RUBBERS AND COLLARS TO ENSURE A TIGHT FIT. THESE BRACKETS WERE A ONE-PIECE AFFAIR, THE JOINTS BEING SEAMLESS. TWO MORE CHROME COVERS WERE USED TO HIDE THE BOTTOM YOKE. THESE WERE DIRECTLY UNDER THE HEADLAMP BRACKETS.THE FORKS COULD BE BOUGHT AS A COMPLETE ASSEMBLY OR IN MANY PIECES, DEPENDING ON WHAT WAS REQUIRED. THE FRONT SUSPENSION WAS CONSIDERED ADEQUATE BUT NOT EXCELLENT. IT WAS BORDERING ON THE SOFT SIDE AND MANY OWNERS REPLACED THE FORK OIL WITH A HEAVIER GRADE. STANDARD WEIGHT WAS 10W. MANY AFTER-MARKET PRODUCTS WERE DEVELOPED FOR THE Z1 FORKS INCLUDING PROGRESSIVE FORK SPRINGS, PRE-LOADERS AND FORK BRACES ALONG WITH LONGER FORK TUBES FOR THAT "CHOPPER" LOOK. THESE WERE VERY POPULAR ON AMERICAN BIKES.THERE WERE NO REPLACEABLE BUSHES IN THE FORKS, SO EXCESSIVE PLAY CAN ONLY BE CURED WITH MAJOR NEW PART REPLACEMENT.

FRONT WHEEL:

THE FRONT WHEEL HAD A CHROMED STEEL 19-INCH RIM MADE BY THE TAKASAGO COMPANY. THIS WAS A 1.85X19 SIZE WITH 40 HOLES. THIS WAS ATTACHED TO THE FRONT WHEEL HUB BY 40 ZINC PLATED "BUTTED" SPOKES.THE HUB ITSELF WAS LIGHT ALLOY ITEM FINISHED IN SATIN BLACK. BOTH SIDES OF THE HUB HAD SIX 8MM HOLES TO WHICH BOLTED THE FRONT DISC ROTORS. THE RIGHT HAND SIDE HOLES WERE BLANKED OFF BY A STAINLESS STEEL COVER WHICH WAS HELD ON BY THREE 5MM CHROME COUNTERSUNK SCREWS. THIS WOULD HAVE TO BE REMOVED IF THE OPTIONAL DOUBLE DISK CONVERSION KIT WAS TO BE FITTED.TWO ROLLER BEARINGS WERE ENCLOSED IN THE HUB WITH A SPACER BETWEEN THEM. BEARING NUMBERS FOR THESE WERE 6203. AN OIL SEAL ON THE RIGHT HAND SIDE KEPT THE GREASE FOR THE BEARINGS IN PLACE. RUNNING THROUGH THE HUB WAS A ZINC PLATED AXLE. THIS SCREWED INTO THE SPEEDOMETER GEARBOX. THE GEARBOX WAS FINISHED IN SATIN BLACK AND HOUSED TWO GEARS, A DRIVE PLATE, AND A GREASE SEAL. A ZINC PLATED SPACER WAS FITTED BETWEEN THE HUB AND THE RIGHT HAND FORK LEG. A BLOB OF YELLOW PAINT WAS APPLIED BY THE FACTORY PRODUCTION LINE TO THE THREADED END OF THE AXLE TO CONFIRM IT WAS TIGHTENED TO THE CORRECT TORQUE.THE FRONT WHEEL WAS FITTED WITH A RIM TAPE, INNER TUBE AND A 3.25HX19 4PR DUNLOP GOLD SEAL F6 TYRE. THIS WAS A RIBBED FRONT TYRE, WHICH KAWASAKI CLAIMED TO ASSIST HIGH SPEED STABILITY. THE STATED AIR PRESSURE FOR THIS TYRE WAS 26PSI. MINIMUM TREAD DEPTH WAS 1MM.

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FRONT FENDER:THIS WAS A CHROME ITEM WHICH WAS FASTENED TO THE FORK LOWERS BY FOUR 8MM BOLTS. SANDWICHED BETWEEN THE FENDER AND LEFT HAND FORK LEG WAS A CHROME BRACKET WHICH HELD THE SPEEDO CABLE AND THE FRONT BRAKE HOSE.THE SUPPLYING DEALER DRILLED MANY FRONT FENDERS IN ORDER TO FIT THE THEN COMPULSORY FRONT NUMBERPLATE. THE MORE THOUGHTFUL DEALER ATTACHED THE PLATE UNDERNEATH THE HEADLAMP OVER THE BRAKE JUNCTION BOX.

FRONT BRAKE:THE Z1 WAS FITTED WITH JUST ONE DISK BRAKE AS STANDARD, A 296MM DISK PLATE. THE STAINLESS DISK WAS ATTACHED TO THE FRONT WHEEL HUB BY SIX 8MM BOLTS. THESE BOLTS WERE SECURED BY THREE ZINC PLATED TABBED LOCKING WASHERS. THE CARRIER OF THE DISK PLATE WAS FINISHED IN SATIN BLACK. THE BOLTS WERE UNUSUAL BECAUSE THEY USED A METRIC THREAD OF 1MM, NOT THE NORMAL 1.25MM. THEY ALSO HAD A HEAD OF 12MM SPANNER SIZE. ATTACHED TO THE RIGHT HAND FORK LOWER BY TWO 10MM CHROME BOLTS WAS A SINGLE BRAKE CALLIPER. THIS WAS A SINGLE PISTON ITEM SO THE BODY OF THE CALLIPER TOGETHER WITH THE TWO BRAKE PADS HAD TO BE FREE TO SLIDE SIDEWAYS ON ITS TWO ZINC PLATED ALLEN BOLT SHAFTS. THESE SHAFTS RAN THROUGH THE HOLDER PLATE AND WERE FITTED WITH O`RINGS AND DUST SEALS. A PISTON SEAL OF 42MM KEPT THE FLUID IN AND A LARGE DUST SEAL KEPT THE ELEMENTS FROM CORRODING THE CHROMED PISTON. THE CALLIPER BODY WAS FINISHED IN SATIN BLACK, AS WAS THE HOLDER BRACKET. THE OUTSIDE OF THE CALLIPER HAD A CIRCULAR DECAL ON IT, PURPLISH BROWN WITH A SILVER EDGE TO IT. THIS WAS MORE OF A DECORATION THAN SERVED A PURPOSE. A BLEED NIPPLE, PROTECTED BY A SMALL BLACK RUBBER CAP, SCREWED INTO THIS OUTER BODY ALONG WITH A SHAPED STEEL PIPE THAT RAN TO THE FLEXIBLE RUBBER BRAKE PIPE. THIS FLEXIBLE PIPE RAN UP TO THE BRAKE JUNCTION BOX WHICH WAS ATTACHED TO THE BOTTOM YOKE BY TWO 6MM CHROME BOLTS. THIS JUNCTION BOX ALSO HELD THE HYDRAULIC FRONT BRAKE LIGHT SWITCH. THIS SWITCH SCREWED INTO THE JUNCTION BOX AND WAS PROTECTED BY A RUBBER COVER AND STRANGELY ENOUGH, IT IS WORTH NOTING THAT IT DOES NOT HAVE A METRIC THREAD. THE JUNCTION BOX WAS FINISHED IN A MATT BLACK ANODISED FINISH. RUNNING FROM THE JUNCTION BOX WAS ANOTHER FLEXIBLE BRAKE PIPE, PROTECTED BY A LONG COILED SPRING. BOTH OF THESE HOSES WERE CONNECTED TO THE JUNCTION BOX BY 10MM ZINC PLATED BANJO BOLTS AND ALUMINIUM FLAT WASHERS. THIS TOP HOSE WAS CONNECTED TO THE HYDRAULIC MASTER CYLINDER BY ANOTHER 10MM BANJO BOLT AND PROTECTED, AT THE END, BY A RUBBER DUST COVER. THE FRONT MASTER CYLINDER WAS A SINGLE PISTON ITEM WITH A SCREWED ON TOP. THIS WAS FASTENED TO THE HANDLEBARS BY TWO 6MM CHROME BOLTS. THE CYLINDER WAS FINISHED IN A BLACK ANODISED COLOUR. WITH AGE THIS FADES TO A SHADE OF PURPLE. THE CYLINDER IS DRILLED ON TOP WITH A 10MM HOLE FOR THE MIRROR MOUNT. THIS IS THE USUAL 1.25MM METRIC THREAD PITCH.MOST MODELS WERE FITTED WITH A SOLID ALL METAL CYLINDER. HOWEVER, SOME MODELS HAD A PLASTIC RESERVOIR. THE SCREW ON TOP WAS EMBOSSED WITH THE WORDS "BRAKE FLUID", WHILE THE AMERICAN MODEL HAD A DECAL STATING WHICH TYPE OF BRAKE FLUID TO USE. RECOMMENDED FLUID WAS TYPE J-1703 OR DOT 3.THE FRONT BRAKE LEVER WAS ADJUSTABLE BY THE USE OF A CONCENTRIC BOLT WHICH WOULD ROTATE TO ELIMINATE ANY EXCESSIVE PLAY.THE FRONT BRAKE PADS WERE FITTED WITH A METAL SHIM WHICH WAS INTENDED TO REDUCE BRAKE SQUEAL. IT DID NOT WORK. EVEN TODAY WITH ALL THE NEW PAD MATERIAL AVAILABLE, THE PROBLEM STILL EXISTS.THE SINGLE DISK SET-UP WAS DESCRIBED BY KAWASAKI AS "RETRO ROCKET." HOWEVER, MOST OWNERS WERE LESS THAN IMPRESSED. THE RIGHT HAND DOUBLE DISK CONVERSION KIT THAT KAWASAKI OFFERED AS AN OPTIONAL EXTRA WAS EXPENSIVE BUT ESSENTIAL. THE COST WAS MORE THAN 10% OF THE TOTAL MOTORCYCLE PURCHASE PRICE. THE PART NUMBER FOR THIS KIT WAS 99990-523. THE KIT CONSISTED OF ANOTHER DISK, EXACTLY THE SAME AS THE LEFT HAND ONE ALREADY FITTED, A RIGHT HAND CALLIPER, A MASTER CYLINDER WITH A BIGGER PISTON, ANOTHER FLEXIBLE BRAKE HOSE, A RIGHT HAND METAL BRAKE PIPE AND ANOTHER BRACKET TO SANDWICH BETWEEN THE FENDER AND THE RIGHT HAND FORK LEG TO HOLD THE NEW BRAKE PIPE. ALSO INCLUDED WAS A FOUR-WAY JUNCTION BOX, ALL THE RELEVANT FITTINGS AND AN INSTRUCTION MANUAL.

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MANY RECENT OWNERS HAVE FOUND IT VERY DIFFICULT TO OBTAIN THE GENUINE KIT AND HAVE RESORTED TO USING A LEFT HAND CALLIPER WHICH CAN BE TURNED AROUND AND MADE TO FIT. A "DOUBLE DISK" MASTER CYLINDER IS ALSO VERY HARD TO OBTAIN, RESULTING IN PARTS FROM MUCH LATER MODELS TO BE USED. ALL "DOUBLE DISK" CYLINDERS HAVE "5/8" STAMPED ON THEM ON THE UNDERNEATH. THIS REPRESENTS THE SIZE OF THE PISTON. SINGLE DISK SIZE IS HALF AN INCH.

HANDLEBARS:THE HANDLEBARS ON THE Z1 WERE CHROME HIGH RISE ITEMS. THESE WERE ATTACHED TO THE TOP YOKE BY TWO SATIN BLACK FINISHED CLAMPS AND WERE FASTENED DOWN WITH FOUR 8MM DOME HEADED CHROME BOLTS. ORIGINALLY THESE HAD A 12MM HEAD BUT NEW REPLACEMENT BOLTS HAVE A 13MM HEAD. THE CENTRE OF THE BARS WERE KNURLED TO ASSIST FIGMENT AND THERE IS A SMALL HOLE DRILLED INTO THE TOP OF THE RIGHT HAND SIDE TO HELP LOCATE THE RIGHT SWITCHGEAR.THE BARS WERE DESIGNED WITH THE AMERICANS IN MIND AND MANY EUROPEAN OWNERS CHANGED THEM FOR LOWER ITEMS. THIS MADE HIGH SPEED TOURING MUCH MORE COMFORTABLE.

SWITCHGEAR AND CONTROLS:

ATTACHED TO THE HANDLEBARS WERE TWO SWITCH CLUSTERS. THE LEFT HAND ONE, WHICH WAS FINISHED IN SATIN BLACK, HAD CONTROLS FOR THE HORN, INDICATORS AND HIGH AND LOW BEAM SELECTION. THE UK MODEL ALSO HAD A FACILITY TO FLASH THE HEADLAMP ON TO HIGH BEAM. THE RIGHT HAND ONE, ALSO FINISHED IN SATIN BLACK, HAD CONTROLS FOR THE LIGHTS, STARTER BUTTON AND THE EMERGENCY ENGINE KILL SWITCH. ON THE UK MODEL THE LIGHT SWITCH COULD BE PAUSED ON THE MIDDLE POSITION TO SELECT "CITY LIGHTS". THIS LIT UP THE SMALL 4-WATT BULB IN THE HEADLAMP FOR RIDING AT DUSK. THE WIRING FOR BOTH THE SWITCHES RAN ALONG THE OUTSIDE OF THE HANDLEBARS OVER THE TOP YOKE AND DISAPPEARED UNDER THE RIGHT HAND SIDE OF THE FUEL TANK WHERE THEY CONNECTED TO THE MAIN LOOM. FOUR BLACK CABLE TIES, TWO ON EACH SIDE, SECURED THE WIRING TO THE HANDLEBARS.THE RIGHT SWITCHGEAR ALSO HELD THE THROTTLE GRIP AND THE TWO THROTTLE CABLES. BETWEEN THE TWO CABLES WAS A FRICTION ADJUSTING SCREW, WHICH COULD BE USED TO HOLD THE REVS AT A GIVEN SPEED. HANDY WHEN YOU WERE SETTING THE CARBURETTORS UP. ATTACHED TO THE LEFT HAND SIDE OF THE HANDLEBARS WAS THE CLUTCH LEVER AND HOLDER. THE HOLDER BRACKET WAS FINISHED IN SATIN BLACK AND HELD ON TO THE BARS BY A 6MM CHROME BOLT. DRILLED INTO THE BRACKET WAS A THREADED 10MM HOLE FOR ATTACHING THE LEFT HAND MIRROR. A CHROME SCREWED ADJUSTER WAS THREADED ONTO THIS BRACKET TO ENABLE ADJUSTMENT OF THE CLUTCH CABLE. A RUBBER HANDGRIP WAS GLUED TO THE END OF THE HANDLEBAR TO MATCH THE THROTTLE GRIP RUBBER ON THE OPPOSITE END.

MIRRORS:THE Z1 WAS FITTED WITH TWO MIRRORS AS STANDARD. THESE WERE BOTH THE SAME DUE TO THE FACT THAT THE HEAD OF THE MIRROR WAS 360 DEGREE ADJUSTABLE, ENABLING LEFT OR RIGHT FIGMENT. THE STEM OF THE MIRROR WAS METAL FINISHED IN GLOSS BLACK WHILE THE HEADS WERE PLASTIC, FINISHED IN SATIN BLACK. THE MIRROR HEADS WERE ADJUSTABLE INTERNALLY GIVING A WIDE FIELD OF VISION. THE ENDS OF THE STEMS WERE FITTED WITH A 10MM THREAD. THE PLASTIC HEADS WERE REMOVABLE FROM THE STEMS BUT COULD NOT BE BOUGHT SEPARATELY. THE MIRRORS WERE FINE AT LOW SPEEDS BUT VIBRATED BADLY ABOVE 4,000 RPM.

INSTRUMENTS:

TWO ROUND CLOCKS WERE FITTED TO THE Z1. THE FACE OF THE INSTRUMENTS WERE IN A CHARCOAL GREY FINISH, NOT QUITE BLACK. THE SPEEDOMETER WAS CALIBRATED TO 160 MPH IN INCREMENTS OF 20 MPH. THERE WAS A TRIP METER WITH A RESET WHEEL ON THE LEFT HAND SIDE OF IT.

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THE TACHOMETER WAS CALIBRATED TO 12,000 RPM AND HAD A RED LINE STARTING AT 9,000.BOTH CLOCK OUTERS WERE FINISHED IN GLOSS BLACK WITH A STAINLESS SECURING RING AROUND THEM. THEY HAD WHITE NEEDLES AND WERE ILLUMINATED BY TWO BULBS EACH. THE NUMERALS ON BOTH METERS WERE FINISHED IN WHITE. ON THE BACK OF EACH METER WAS A DOMED, GLOSS BLACK FINISHED, COVER. A SMALL 3MM PAN HEAD SCREW HELD THESE ONTO THE METER. THE COVER OVER THE BACK OF THE SPEEDO HAD A SMALL CUT OUT SLOT FOR THE RESET WHEEL. THE METERS WERE ATTACHED TO AN ALLOY BRACKET WITH A SERIES OF RUBBERS, COLLARS, NUTS, AND WASHERS. THE END RESULT WAS A SLIGHTLY LOOSE EFFECT TO COMBAT VIBRATION. THIS BRACKET WAS FINISHED IN SATIN BLACK AND WAS BOLTED TO THE TOP YOKE WITH TWO 8MM ZINC PLATED BOLTS. THE TOP FACE OF THE METER BRACKET WAS COVERED WITH A THIN LAYER OF FOAM RUBBER, WHICH ACTED AS A VIBRATION DAMPER.BETWEEN THE TWO METERS WAS AN "IDIOT LIGHT" COVER. THIS HOUSED THE IGNITION SWITCH AND THE WARNING LIGHT CLUSTER. THE IGNITION SWITCH HAD THREE POSITIONS. OFF, ON AND PARK. ABOVE THE SWITCH WAS A SMALL HOLE. A STICKER ABOVE THIS CLAIMED IT WAS A KEY HOLDER. HOWEVER, IT WAS NEVER USED AS SUCH. NO ONE IN THEIR RIGHT MIND WOULD HAVE LEFT THEIR KEY IN THERE! THEY OBVIOUSLY HAD NEVER HEARD OF BIKE THEFT IN JAPAN!BELOW THE SWITCH RAN A SERIES OF FOUR COLOURED WARNING PANELS. THESE WERE, IN ORDER FROM LEFT TO RIGHT, NEUTRAL, FLASH, HIGH BEAM, AND OIL. DIRECTLY BELOW THIS COVER WAS ANOTHER PLASTIC COVERING WHICH HID ALL THE WIRING FROM VIEW. THREE SMALL 3MM PAN HEAD SCREWS ATTACHED THIS TO THE CLOCK MOUNTING BRACKET.THE Z1 INSTRUMENT CONSOLE HAS BECOME SOMETHING OF AN ICON AND IS OFTEN DUPLICATED IN MANY MODERN DESIGNS SUCH AS THE KAWASAKI ZEPHYR RANGE. ONCE AGAIN PROVING THE LASTING EFFECT THE Z1 HAD ON THE WORLD.

HEADLAMP:THE HEADLAMP ON THE Z1 VARIED FROM COUNTRY TO COUNTRY. THE SHELL HOWEVER WAS THE ALWAYS THE SAME. THIS WAS A SATIN BLACK FINISHED ITEM WITH ONE LARGE HOLE IN THE REAR, TO ALLOW THE WIRING TO RUN THROUGH IT. ON THE TOP OF THE SHELL WAS ANOTHER SMALL HOLE, WHICH WAS PLUGGED WITH A RUBBER BUNG. THIS HOLE WAS TO ALLOW THE FITTING OF THE SPEED WARNING LIGHT OF THE Z2-750 MODEL. THE SHELL WAS ALSO USED ON THE H2-750 TRIPLE AND THIS HOLE HOUSED THE HIGH BEAM WARNING LIGHT ON THIS MODEL.THE FRONT SECTION OF THE HEADLAMP IN THE UK CONSISTED OF A CHROME OUTER RIM WHICH WAS SECURED TO THE SHELL BY TWO 5MM COUNTER SUNK PAN HEAD SCREWS. THE LENS UNIT WAS A 7-INCH UNIT MADE BY THE `KOITE` COMPANY WITH A REMOVABLE BULB HOLDER FOR THE MAIN BULB AND ONE FOR THE SMALL PARKING LIGHT BULB. AMERICAN HEADLAMPS USED A SEALED BEAM UNIT, WHICH MEANT A COMPLETE REPLACEMENT WAS NEEDED IF THE BULB FAILED. THERE WAS NO PARKING LIGHT FITTED TO THIS UNIT.ANOTHER INNER RIM WAS ATTACHED SO THAT A LONG 4MM PAN HEAD SCREW COULD MAKE VERTICAL ADJUSTMENT. THE HEADLAMP WAS CONSIDERED TO BE VERY POOR AT THE TIME DUE TO THE USE OF A LOW 40/45-WATT BULB. SOME OF THE AMERICAN UNITS WERE EVEN WORSE AND USED A PITIFUL 35-WATT BULB. MANY OWNERS REPLACED THE HEADLAMP WITH AN AFTERMARKET QUARTZ HALOGEN UNIT, WHICH WAS FAR SUPERIOR. A SMALL BLACK METAL BRACKET WAS BOLTED TO THE BOTTOM OF THE HEADLAMP SHELL BY A 8MM ZINC PLATED BOLT AND FASTENED AT THE OTHER END BETWEEN THE BRAKE JUNCTION BOX AND BOTTOM YOKE TO ADD SUPPORT AND ADJUSTMENT TO THE HEADLAMP. THIS BRACKET WAS REMOVED ON LATER MODELS BECAUSE IT WAS FOUND TO BE CONTRIBUTING TO BULB FAILURE DUE TO VIBRATION. THE HEADLAMP UNIT WAS THEN SANDWICHED BETWEEN THE TWO BRACKETS ON THE FRONT FORKS BY A SERIES OF RUBBER MOUNTS. THE TWO CHROME INDICATOR STEMS PUSHED THROUGH THESE BRACKETS AND THEN THROUGH THE HEADLAMP SHELL AND BOLTED THE WHOLE LOT TOGETHER. TWO ALLOY EARTHING COLLARS INSIDE THE SHELL ACTED AS SPACERS WHILE EVERYTHING WAS TIGHTENED AND SECURED BY TWO 10MM NUTS.

INDICATORS:

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THE Z1 WAS FITTED WITH FOUR CHROME INDICATORS MADE BY THE STANLEY COMPANY. THESE WERE FITTED WITH 12V 21W BULBS IN THE UK BUT OTHER MARKETS USED BULBS BETWEEN 18W AND 23W. THE ORANGE LENSES WERE SECURED TO THE BODY BY TWO 4MM CHROME PAN HEAD SCREWS. 6MM X 32MM CHROME BOLTS, NUTS, AND WASHERS THEN CLAMPED THESE TO THE FOUR CHROME STEMS. THE STEMS WERE RUBBER MOUNTED TO THE HEADLAMP AT THE FRONT AND THROUGH HOLES IN THE FRAME AT THE REAR. EARTH LEADS WERE FITTED TO ALL STEMS AND A SINGLE WIRE RAN FROM EACH INDICATOR TO THE MAIN WIRING LOOM. A SMALL FLASHER RELAY WAS RUBBER MOUNTED TO THE TOOLBOX UNDERNEATH THE RIGHT HAND SIDE PANEL. TWO WIRES RAN FROM THE MAIN LOOM TO THIS UNIT.ALL FOUR INDICATORS HEADS AND LENSES WERE EXACTLY THE SAME.

REAR LIGHT:

THE TAILLIGHT UNIT ON THE Z1 WAS AN OVAL SHAPE WITH A BUILT IN REFLECTOR. THE RED LENS WAS SCREWED TO ITS CHROME BACKING PLATE BY TWO 4MM PAN HEAD SCREWS. THE BULB USED IN THE UK WAS A TWIN FILAMENT 12V 21/5W. THIS ASSEMBLY WAS THEN BOLTED TO THE TAILLIGHT BRACKET BY THREE 6MM BOLTS. THE BRACKET WAS FINISHED IN SATIN BLACK AND BOLTED TO THE REAR FENDER BY ANOTHER THREE 6MM BOLTS. BETWEEN THE BRACKET AND THE FENDER WAS A BLOCK OF RUBBER, WHICH HELPED TO DAMPEN THE VIBRATION.THERE WAS TWO DIFFERENT TYPES OF BRACKETS. ONE FOR THE LONG REAR FENDER AND ONE FOR THE SHORT FENDER. THEY HELD THE TAILLIGHT AT DIFFERENT ANGLES DUE TO THE DIFFERENCE IN THE SHAPE OF THE FENDERS. THIS ENSURED THAT THE TAILLIGHT SAT SNUGLY UNDERNEATH THE REAR TAIL FAIRING.A SMALL WIRING LOOM THEN RAN FROM THE TAILLIGHT ASSEMBLY TO THE MAIN WIRING LOOM CONNECTING UNDER THE SEAT WITH A MALE AND FEMALE SIX PIN BLOCK CONNECTOR. THE BRAKE LIGHT WAS ACTIVATED BY THE HYDRAULIC SWITCH AT THE FRONT AND BY A MECHANICAL SWITCH AT THE REAR.

REAR BRAKE PEDAL:THIS WAS A CHROME UNIT AND PIVOTED ON A SHAFT WELDED TO THE MAIN FRAME. A WASHER AND AN 8MM DOME NUT SECURED IT TO THIS SHAFT. A LARGE COILED SPRING HELPED TO RETURN THE PEDAL ONCE IT HAD BEEN DEPRESSED. A SMALL 6MM BOLT SCREWED INTO THE FRAME, ABOVE THE PEDAL, TO ACT AS A STOP AND DOUBLED AS AN ADJUSTER.ATTACHED TO THE REAR OF THE PEDAL WAS THE ZINC PLATED BRAKE ROD WHICH RAN BACKWARDS TO THE REAR BRAKE PANEL ON THE RIGHT HAND SIDE OF THE REAR WHEEL. THE ROD WAS THREADED ON BOTH ENDS TO ENABLE ADJUSTMENT. THIS THREAD WAS 6MM. RUNNING FROM THE PEDAL WAS A SPRING AND A SMALL METAL HOOK, WHICH ACTIVATED THE REAR BRAKE LIGHT SWITCH. THIS SWITCH WAS FIXED TO THE RIGHT HAND REAR ENGINE MOUNTING BRACKET AND WAS ADJUSTED BY TWO THIN 12MM NUTS. TWO WIRES RAN FROM THIS SWITCH TO THE MAIN WIRING LOOM.

OTHER ELECTRICAL COMPONENTS:

THE MAIN WIRING LOOM ON THE Z1 RAN FROM THE HEADLAMP SHELL BACKWARDS TO THE REAR FENDER. FROM THE SHELL IT PASSED OVER THE LEFT HAND SIDE OF THE HEADSTOCK UNDERNEATH THE PETROL TANK AND DOWN TOWARDS THE RIGHT HAND SIDE PANEL. HERE IT MEETS UP WITH THE CENTRE LOOM, WHICH CONSISTS OF A SERIES OF FOUR COLOURED PLUG CONNECTORS. ONE WHITE, ONE GREEN, ONE BLUE AND ONE BROWN. IT THEN CARRIES ON TO MEET UP WITH THE TAILLIGHT LOOM. PLASTIC CABLE TIES HOLD IT TO THE FRAME IN VARIOUS LOCATIONS.UNDERNEATH THE RIGHT HAND SIDE PANEL WAS THE MAIN ELECTRICAL PANEL. ATTACHED TO THIS PANEL WAS THE CENTRE LOOM, VOLTAGE RECTIFIER, STARTER SOLENOID SWITCH AND

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THE MAIN FUSE HOLDER. THIS PANEL WAS RUBBER MOUNTED AND BOLTED TO THE SIDE OF THE BATTERY BOX BY TWO 6MM BOLTS.THE RECTIFIER WAS RUBBER MOUNTED TO THE BRACKET AND HELD BY TWO 6MM NUTS. A WHITE PLUG CONNECTED IT TO THE CENTRE LOOM. THE SINGLE 20 AMP FUSE WAS HOUSED IN A WHITE PLASTIC HOLDER AND CONNECTED BETWEEN THE POSITIVE BATTERY LEAD AND THE RECTIFIER. A SMALL RUBBER HOLDER HELD THE FUSE IN PLACE AND ALSO HELD TWO SPARE 20 AMP FUSES.THE STARTER SOLENOID SWITCH WAS RUBBER MOUNTED TO THE BRACKET AND HELD BY TWO 6MM BOLTS AND CONNECTED TO THE CENTRE LOOM BY TWO WIRES. THE SWITCH ITSELF HAD TWO LEADS CONNECTED TO IT, ONE TO THE STARTER MOTOR AND THE OTHER TO THE POSITIVE SIDE OF THE BATTERY.CONNECTED TO THE GREEN PLUG ON THE CENTRE LOOM WAS THE VOLTAGE REGULATOR. THIS WAS RUBBER MOUNTED TO THE BOTTOM OF THE BATTERY BOX AND HELD BY TWO 6MM BOLTS.THE BROWN PLUG ON THE PANEL WAS CONNECTED TO THE MALE BROWN PLUG FROM THE MAIN WIRING LOOM. THE REMAINING BLUE PLUG WAS CONNECTED TO THE ALTERNATOR SITUATED ON THE LEFT HAND SIDE OF THE ENGINE.THE BATTERY WAS A 12V 14 AMP YUASA LEAD ACID UNIT. THE NEGATIVE LEAD FROM THE BATTERY RAN DOWN TO CONNECT TO THE REAR OF THE ENGINE CRANKCASE. ANOTHER WIRE RAN FROM THIS LEAD TO THE MAIN LOOM ACTING AS AN EXTRA EARTH. THE BATTERY SAT IN A PLASTIC TRAY WHICH IN TURN SAT INTO THE BATTERY BOX. AN OVERFLOW PIPE RAN FROM THE BATTERY DOWN TOWARDS THE REAR SWING ARM.THE Z1 WAS EQUIPPED WITH A 12V 2.5AMP HORN WHICH WAS FIXED BY AN 8MM BOLT TO THE FRAME UNDERNEATH THE HEADSTOCK. THE FINISH ON THE HORN WAS A SATIN BLACK PAINT. THE BRACKET HOLDING THE HORN TO THE FRAME WAS ORIGINALLY A THREE-PIECE LEAF AFFAIR, BUT IN ORDER TO INCREASE PERFORMANCE KAWASAKI MODIFIED IT TO A FOUR-PIECE UNIT. THIS TOOK PLACE IN DECEMBER 1973 FROM FRAME NUMBERS Z1F-31667 ONWARDS. A NEW COMPLETE HORN WAS MADE AVAILABLE UNDER THE NEW PART NUMBER 27003-053.TWO WIRES RAN FROM THE HORN, A BLACK ONE TO THE LEFT HAND SWITCHGEAR AND THE OTHER, A BROWN ONE, TO THE MAIN LOOM.

THE Z1 WAS EQUIPPED WITH A 12V ELECTRIC STARTER MOTOR MADE BY THE MITSUBA COMPANY OF JAPAN. MODEL NUMBER FOR THIS MOTOR WAS SM-226-K.A SINGLE LEAD FROM THIS MOTOR RAN TO THE STARTER SOLENOID SWITCH. IT WAS BOLTED TO THE TOP OF THE CRANKCASES BY TWO 6MM BOLTS AND COVERED BY A CHROME METAL COVER, ITSELF SECURED BY TWO CHROME 6MM BOLTS.IT WAS A CONVENTIONAL DIRECT CURRENT MOTOR AND CONNECTED TO AN IDLER GEAR WHICH IN TURN CONNECTED TO A MUCH LARGER GEAR WHICH OPERATED THE ONE WAY STARTER CLUTCH INSIDE THE LEFT HAND SIDE ALTERNATOR CASING.

PROBLEMS WERE REPORTED OF EXCESSIVE BULB BLOWING AND KAWASAKI DECIDED THE FAULT WAS DUE TO POOR EARTHING OF THE VOLTAGE REGULATOR UNIT. A MODIFIED UNIT WAS PRODUCED WITH A SEPARATE BLACK EARTH WIRE, WHICH WAS TO BE CONNECTED DIRECTLY TO EITHER THE POSITIVE BATTERY TERMINAL OR THE EARTH MOUNTING POINT ON THE CRANKCASES. THE MODIFIED PART WAS GIVEN THE PART NUMBER 21066-019. THE OLD NUMBER WAS 21066-013. THE IDENTIFICATION NUMBER ON TOP OF THE MODIFIED REGULATOR WAS RS 2123.THE HEADLAMP MOUNTING RUBBERS WERE ALSO MODIFIED TO A SOFTER COMPOUND IN AN EFFORT TO REDUCE VIBRATION. NONE OF THESE MODIFICATIONS PROVED TO BE SUCCESSFUL AND IT WOULD BE MANY YEARS BEFORE THE PROBLEM WAS SOLVED.

REAR FENDER:

THERE WAS TWO DIFFERENT TYPES OF REAR FENDERS FITTED TO THE Z1. A LONG ONE AND A SHORT ONE. THE UK VERSION WAS THE LONG ONE WHILE THE AMERICAN MODEL GOT THE SHORTER SPORTIER ITEM. THEY WERE BOTH FINISHED IN BRIGHT CHROME. THE FENDER WAS ATTACHED TO THE FRAME BY SIX 6MM BOLTS. THE FRONT TWO BOLTS FASTENED THROUGH A SERIES OF RUBBER MOUNTS, THROUGH THE FRAME AND INTO CAPTIVE NUTS IN THE FENDER ITSELF. SANDWICHED BETWEEN THE FRAME AND FENDER WAS A PLASTIC INNER FENDER WHICH

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RAN DOWN TO THE REAR SWINGING ARM. THIS STOPPED ANY DEBRIS FROM REACHING ANYWHERE UNDERNEATH THE SEAT AREA. ANOTHER RUBBER MOUNTED BRACKET WRAPPED AROUND THE REAR FRAME LOOP AND BOLTED TO THE FENDER, USING THE OTHER FOUR BOLTS, HOLDING IT SECURELY IN PLACE.THE TAILLIGHT BRACKET WAS THEN BOLTED TO THE FENDER.BELOW THIS BRACKET, ON THE SHORT FENDERS, WAS A SMALL HOLE, WHICH HELD A SMALL RUBBER BUNG. THIS BUNG WAS TO STOP THE REAR NUMBERPLATE FROM HITTING THE FENDER AND CAUSING VIBRATION.TWO MORE RUBBER DAMPERS PUSHED INTO THE SIDE OF THE FRAME AND CUSHIONED THE FENDER SIDEWAYS.STUCK ONTO THE TOP OF THE INNER PLASTIC FENDER WAS A SERIES OF WARNING STICKERS. THESE WERE INFORMATION FOR DRIVE CHAIN, TYRE AND LOAD DATA AND ON THE UK MODEL, BRAKE FLUID REQUIREMENTS.

REAR SUSPENSION:

TWO OIL FILLED SHOCK ABSORBERS WERE FITTED TO THE Z1. THESE WERE CHROME UNITS AND WERE ADJUSTABLE FOR PRE-LOAD BY A FIVE WAY ADJUSTER AT THE BOTTOM OF EACH SHOCK. THEY WERE EYED AT EACH END AND THE TOP OF EACH UNIT PUSHED ONTO STUDS ON THE MAIN FRAME. THEY WERE THEN SECURED BY TWO 12MM CHROME DOMED NUTS AND WASHERS. TWO CHROME 10MM BOLTS SECURED THE BOTTOM MOUNTS TO THE REAR SWING ARM. THE UK MODEL HAD PLAIN CHROMED METAL SHROUDS ON THE TOP OF THE SHOCKS WHILE THE AMERICAN MODEL HAD CHROMED PLASTIC SHROUDS INCORPORATING A SCREW ON RED REFLECTOR. THESE SHOCK ABSORBERS WERE CONSIDERED A WEAK SPOT ON THE Z1 AND MANY OWNERS REPLACED THEM WITH SUPERIOR AFTER MARKET ITEMS.

FOOTREST:

ON EACH SIDE OF THE MAIN FRAME, THERE WERE TWO STUDS WHICH SCREWED INTO THE FRAME AND WERE SECURED BY 10MM NUTS AT THE REAR. THE FRONT FOOTREST BRACKETS WERE THEN MOUNTED TO THESE STUDS USING RUBBER BUSHES TO REDUCE VIBRATION. A DOMED WASHER AND 8MM-DOMED NUT THEN WENT ONTO EACH STUD TO SECURE THE BRACKETS. THE BRACKETS WERE FINISHED IN SATIN BLACK.THE UK MODEL HAD NON-FOLDING FOOTREST AND USED JUST A RUBBER WHICH PUSHED ONTO THE METAL BRACKET.THE AMERICAN MODEL USED FOLDING RUBBER FOOTREST, WHICH PIVOTED ONTO THE MAIN BRACKET BY THE USE OF A CLEVIS PIN. A LARGE WASHER WENT BETWEEN THE BRACKET AND THE RUBBER AND A SMALL COTTER PIN SECURED THE CLEVIS PIN IN PLACE.THE REAR FOOTREST CONSISTED OF A BLACK METAL BRACKET, WHICH SCREWED INTO THE REAR FRAME SECTION. A 12MM CHROME NUT WAS THEN USED TO TIGHTEN THIS BRACKET IN THE DESIRED POSITION. A CHROMED METAL STEM THEN PIVOTED ON THIS BRACKET USING A SMALL CLEVIS PIN, WASHER, AND SPLIT PIN. OVER THIS STEM THEN WENT THE FOOTREST RUBBER LEAVING THE EXPOSED CHROMED END OF THE STEM TO SHOW THROUGH.

STANDS:

THE Z1 WAS FITTED WITH TWO STANDS. A SIDE STAND AND A MAIN CENTRE STAND.THE SIDE STAND WAS FINISHED IN GLOSS BLACK AND WAS SECURED TO THE FRAME BY A SHOULDERED ZINC PLATED 10MM BOLT AND 10MM NUT. A ZINC PLATED RETURN SPRING ATTACHED TO THE STAND AND THEN ONTO A PEG ON THE MAIN FRAME. THE MAIN STAND WAS FINISHED IN GLOSS BLACK AND WAS ATTACHED TO THE MAIN FRAME BY TWO ZINC PLATED SHOULDERED BOLTS AND NUTS. THESE RAN THROUGH TWO LOOPED BRACKETS ON THE UNDERSIDE OF THE FRAME. A SINGLE ZINC PLATED RETURN SPRING WAS FITTED BETWEEN THE TWO BOLTS.ON THE ORIGINAL 1972/1973 Z1, THESE SHOULDERED BOLTS WERE HOLLOW. LATER MODELS WENT TO A SOLID DESIGN BUT KEPT THE SAME PART NUMBER.

ENGINE MOUNTINGS:

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THE ENGINE WAS BOLTED TO THE FRAME IN FIVE DIFFERENT POINTS. THE ENGINE WAS INTENDED TO BE REMOVED FROM THE LEFT HAND SIDE OF THE FRAME, SO THE MOUNTING POINTS ON THE RIGHT HAND SIDE WERE FIXED.THERE WERE TWO TRIANGULAR PLATES BOLTED TO THE FRAME ON THE RIGHT HAND SIDE, ONE ON THE DOWN TUBE AND A SMALLER ONE JUST BELOW THE CLUTCH COVER. THE LARGER PLATE WAS SECURED WITH TWO ZINC PLATED 8MM BOLTS, ONE 56MM LONG, AND THE OTHER 63MM LONG. TWO 8MM NUTS ALONG WITH WASHERS TIGHTENED THEM UP. THE BOTTOM SMALLER PLATE WAS SECURED WITH TWO ZINC PLATED 8 X 18 MM BOLTS WHICH SCREWED DIRECTLY INTO THE FRAME.THERE WAS TWO MORE REAR ENGINE MOUNTING PLATES THAT WERE BOLTED TO THE REAR FRAME TUBES BY FOUR 8 X 40 MM BOLTS. THESE PLATES HAD 8MM CAPTIVE NUTS BUILT INTO THEM. BOTH PLATES HAD A RUBBER GROMMET ON THEM, WHICH HELD THE FRONT MOUNTING LUGS OF THE SIDE PANELS. THE RIGHT HAND PLATE ALSO HAD A FORKED BRACKET TO HOLD THE REAR BRAKE LIGHT SWITCH.ALL THESE PLATES WERE FINISHED IN GLOSS BLACK PAINT.

THE FRONT TOP ENGINE MOUNTING WAS A ZINC PLATED 10 X 310 MM LONG BOLT. IT PASSED THROUGH THE FRAME AND CRANKCASES AND THEN THROUGH THE LARGE REMOVABLE TRIANGULAR PLATE ON THE RIGHT HAND SIDE. A 10MM LOCKING NUT THEN SECURED IT.THE LEFT HAND BOTTOM MOUNTING WAS A 12MM ZINC PLATED BOLT WHICH RAN THROUGH THE FRAME AND INTO THE CRANKCASES AND WAS SECURED BY A SPECIAL PEAR SHAPED 12MM NUT. THE SHAPE OF THIS NUT ENSURED THAT IT WOULD SELF LOCK AGAINST THE CRANKCASES.THE RIGHT HAND BOTTOM MOUNTING WAS THE SAME SET UP BUT THIS TIME IT RAN THROUGH THE SMALL REMOVABLE TRIANGULAR PLATE BEFORE ENTERING THE CRANKCASES.THE BOTTOM REAR MOUNTING USED A 10 X 165 MM ZINC PLATED BOLT AND WAS SECURED AT THE OTHER SIDE BY A 10MM LOCKING NUT.THE TOP REAR MOUNTING USED A 10 X 250 MM ZINC PLATED BOLT. BETWEEN THE CRANKCASES AND THE REAR MOUNTING PLATES WERE TWO ZINC PLATED SPACERS. THE LEFT HAND SPACER WAS 52MM LONG WHILE THE RIGHT HAND SIDE ONE WAS 31MM LONG. THIS SHORTER SPACER HAD A RUBBER CLAMP ATTACHED TO IT, WHICH HELD THE CARBURETTOR OVERFLOW PIPES. A 10MM LOCKING NUT TIGHTENED EVERYTHING TOGETHER.

OTHER FRAME FITTINGS:

GRAB RAIL:THE Z1 WAS FITTED WITH A CHROMED PASSENGER GRAB RAIL. THIS WAS FASTENED TO THE TOP REAR SHOCK ABSORBER MOUNTINGS BETWEEN THE SHOCK AND THE DOMED NUT. A FURTHER TWO MORE 10MM BOLTS SCREWED INTO THE GRAB RAIL, A LITTLE FURTHER BACK, FROM INSIDE THE FRAME AND TIGHTENED IT ALL UP. SANDWICHED BETWEEN THE GRAB RAIL AND FRAME AT THIS POINT WAS TWO LARGE ZINC PLATED 10MM FLAT WASHERS.

BATTERY BOX:THE BATTERY BOX WAS FINISHED IN GLOSS BLACK AND WAS RUBBER MOUNTED TO THE MAIN FRAME UNDERNEATH THE SEAT AREA BY TWO 6MM BOLTS. TWO MORE RUBBER MOUNTS HELD THE BOX SECURE TO THE SIDE OF THE FRAME. THE BATTERY WAS HELD IN PLACE BY A LARGE RUBBER STRAP, WHICH STRETCHED ACROSS THE TOP OF THE BATTERY BOX. FOUR FLAT RUBBER DAMPERS SAT AT THE BASE OF THE BOX TO CUSHION THE BATTERY.ATTACHED TO THE FRONT OF THE BOX BY TWO 6MM BOLTS WAS THE AIR BOX HOLDING PLATE. THIS WAS FINISHED IN GLOSS BLACK. THE BRACKET HAD TWO BUILT IN CLAMPS UNDERNEATH IT THAT HELD THE STARTER MOTOR WIRE ON ITS WAY TO THE STARTER SOLENOID SWITCH.ATTACHED TO THE REAR OF THE BOX BY TWO 6MM BOLTS WAS THE TOOL TRAY. THIS WAS FINISHED IN GLOSS BLACK. THE TOOLBOX HAD A SMALL ROUND HOLE IN IT WHERE THE BATTERY BREATHER PIPE RAN THROUGH. ON THE RIGHT HAND SIDE OF THE TOOLBOX WAS A SMALL METAL BRACKET, WHICH THE FLASHER RELAY MOUNTED TO. ON THE LEFT HAND SIDE WAS ANOTHER BRACKET, WHICH HELD THE CHAIN OILER OVERFLOW PIPE.ATTACHED TO THE RIGHT HAND SIDE OF THE BATTERY BOX WAS THE MAIN ELECTRICAL PANEL BRACKET. THIS WAS ALSO FINISHED IN GLOSS BLACK.ATTACHED TO THE LEFT HAND SIDE OF THE BATTERY BOX BY TWO 6MM BOLTS WAS A ZINC PLATED BRACKET WHICH HELD THE REAR DRIVE CHAIN OILER BOTTLE. THIS BRACKET HAD THREE HOLES IN IT WHERE THREE RUBBER DAMPERS SAT.

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RUBBER MOUNTED UNDERNEATH THE BATTERY BOX BY TWO 6MM BOLTS WAS THE VOLTAGE REGULATOR.

REAR SWINGING ARM:

THIS WAS A TUBULAR DESIGN AND FINISHED IN GLOSS BLACK. ALTHOUGH BRACED AT THE FRONT IT WAS CONSIDERED TO BE ANOTHER OF THE Z1`S WEAK SPOTS. MANY AFTER MARKET SWING ARMS WERE AVAILABLE FOR THE Z1, THE MOST FAMOUS PERHAPS BEING THE DRESDA BOX SECTION. MOST REPLACEMENTS WERE "MORE SHOW THAN GO", BUT THIS WAS AN AREA THAT CERTAINLY NEEDED TO BE IMPROVED ON.THE ARM RAN ON A SET UP OF PHOSPHOR BRONZE BUSHES AND SLEEVES. ONE BUSH AND ONE SLEEVE ON EACH END. IN BETWEEN THE BUSHES WAS A STEEL SPACER. A GREASE NIPPLE WAS FITTED ON TOP OF THE FRONT OF THE ARM AND A ZINC PLATED CAP AND O`RING KEPT THE GREASE IN PLACE AT EACH END. THIS WAS THEN SECURED TO THE FRAME BY A LONG ZINC PLATED SHAFT BOLT AND CHROME PLATED 16MM LOCKING NUT.THERE WAS TWO BRACKETS ON THE LEFT HAND SIDE OF THE ARM TO WHICH THE CHAIN GUARD FIXED. THESE BRACKETS WERE DRILLED WITH 6MM THREADED HOLES.ON EACH SIDE OF THE REAR OF THE ARM WAS A "U" SHAPED 10MM-THREADED BRACKET, WHICH WERE THE MOUNTINGS FOR THE REAR SHOCK ABSORBERS.UNDERNEATH ON THE RIGHT HAND SIDE OF THE ARM WAS ANOTHER BRACKET WITH A 12MM HOLE THROUGH IT. THROUGH THIS HOLE PASSED A SHOULDERED 10MM ZINC PLATED BOLT AND NUT. THE BOLT WAS DRILLED WITH A SMALL HOLE THROUGH WHICH PASSED A SMALL R-CLIP. THIS BOLT WAS TO HOLD THE CHROME PLATED REAR BRAKE TORQUE ARM. THE TORQUE ARM THEN RAN BACK TOWARDS THE REAR BRAKE PANEL WHERE IT FASTENED TO THE BRAKE PANEL BY ANOTHER 10MM ZINC PLATED BOLT, NUT, AND R-CLIP.THE TORQUE ARM WAS 370MM LONG, FLAT IN DESIGN AND HAD A HOLE DRILLED IN EACH END. THE INSIDE OF THE ARM WAS STAMPED WITH AN IDENTIFICATION MARK, NORMALLY A ONE OR TWO DIGIT NUMBER.THE END OF THE SWING ARM HAD AN OPEN-ENDED FORK DESIGN. INTO THIS OPEN END WENT TWO STOPPERS WHICH BOLTED TO THE ARM BY TWO 8MM ZINC PLATED BOLTS. THIS DESIGN ENABLED THE REMOVAL OF THE STOPPERS SO THAT THE REMOVAL OF THE REAR WHEEL COULD BE MADE WITHOUT HAVING TO REMOVE THE MUFFLERS. THE REAR AXLE COULD NOT BE REMOVED WITH THE MUFFLERS IN PLACE.

REAR WHEEL:

THE REAR WHEEL WAS AN 18 INCH ONE. A CHROME 215X18, 40 HOLE RIM MADE BY THE TAKASAGO COMPANY WAS ATTACHED TO THE LIGHT ALLOY HUB BY 40 ZINC PLATED BUTTED SPOKES. THE OUTSIDE OF THE HUB WAS RIBBED TO ASSIST COOLING AND WAS FINISHED IN A NATURAL ALUMINIUM FINISH. IT CONTAINED TWO 6304 ROLLER BEARINGS AND A STEEL SPACER COLLAR. THE WHEEL WAS FITTED WITH A RIM TAPE, INNER TUBE AND A 400HX18 4PR DUNLOP K87 MK11 TYRE. RECOMMENDED AIR PRESSURE WAS 31 PSI AND MINIMUM TREAD WEAR LIMIT WAS 2MM. THE RIM WAS FITTED WITH TWO BEAD PROTECTORS, WHICH HELPED TO STOP THE TUBE AND TYRE FROM MOVING UNDER SEVERE ACCELERATION. THESE PROTECTORS WERE NOT SHOWN ON THE PARTS BOOK BUT THEY WERE AVAILABLE UNDER THE PART NUMBER 41024-008.IT IS WORTH NOTING THAT THE PARTS BOOK GIVES THE WRONG NUMBER FOR THE REAR WHEEL RIM. THE NUMBER QUOTED IS 41025-052, WHICH IS ACTUALLY A FRONT RIM FOR AN S1-250. THE CORRECT NUMBER IS 41025-049.

SIX CUSH DRIVE RUBBERS SEATED INTO THE LEFT HAND SIDE OF THE HUB AND PUSHED INTO THESE WAS THE LIGHT ALLOY SPROCKET CARRIER ALSO FINISHED IN NATURAL ALUMINIUM. BETWEEN THE HUB AND THE CARRIER WAS A SMALL ALLOY SPACER. THE CARRIER HELD A 6206 ROLLER BEARING AND A GREASE SEAL. ANOTHER SMALL ALLOY SPACER FITTED INTO THIS SEAL AND SPACED THE CARRIER AWAY FROM THE SWING ARM. THE REAR SPROCKET WAS FASTENED TO THE CARRIER BY SIX 10MM ZINC PLATED BOLTS, SIX 10MM NUTS AND THREE LOCKING TAB WASHERS.

THROUGH THE WHEEL RAN A 20MM ZINC PLATED AXLE. THERE WAS ANOTHER ALLOY SPACER BETWEEN THE BRAKE PANEL AND THE RIGHT HAND SIDE OF THE SWING ARM.

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THE THREADED END OF THE AXLE PROTRUDED THROUGH THE RIGHT HAND SIDE OF THE SWING ARM AND WAS SECURED WITH AN 18MM ZINC PLATED CASTLE NUT AND THICK WASHER. THIS WASHER WAS AVAILABLE IN TWO WIDTHS, 4.5MM AND 6MM. THIS ALLOWED ANY EXCESSIVE THREAD TO BE TAKEN UP. THIS WAS THEN SECURED WITH A 4MM X 35MM COTTER PIN.

REAR BRAKE:

THE REAR BRAKE PANEL WAS FITTED INTO THE RIGHT HAND SIDE OF THE REAR WHEEL HUB AND WAS FINISHED IN NATURAL ALUMINIUM.IT WAS A SINGLE LEADING SHOE DRUM BRAKE, 200MM IN DIAMETER AND 35MM WIDE. IT HAD TWO PIVOT PINS, ONE FOR EACH BRAKE SHOE, LINKED AT THEIR OUTER ENDS FOR ADDED RIGIDITY. A LARGE SHAPED WASHER AND TWO COTTER PINS HELD THE SHOES ONTO THE PINS. THE SHOES HAD TWO STRONG SPRINGS BETWEEN THEM TO ASSIST IN CLOSURE. A CAMSHAFT RAN THROUGH THE PLATE AND ATTACHED TO THIS BY AN 8MM BOLT WAS A CHROME ACTUATING LEVER. BETWEEN THE LEVER AND THE CAM WAS A FELT GREASE SEAL HELPING TO KEEP THE CAMSHAFT LUBRICATED. THE LEVER WAS ATTACHED AT THE BOTTOM TO THE BRAKE ROD AND A 6MM-KNURLED THUMBED WHEEL MADE ADJUSTMENT. A SMALL THIN COILED SPRING FURTHER UP THE ROD HELPED IN RETURNING THE BRAKE PEDAL.THE BOTTOM OF THE PANEL WAS DRILLED WITH A 10 MM HOLE. THIS WAS WHERE THE TORQUE ARM BOLT WAS FITTED.THERE WAS NO WEAR INDICATOR ON THE BRAKE PANEL SO OWNERS HAD TO INSPECT THE SHOES FROM TIME TO TIME FOR EXCESSIVE WEAR.

SEAT ASSEMBLY:

THERE WERE TWO TYPES OF SEATS FITTED TO THE Z1. THE UK MODEL SEAT HAD A STRAP AND CHROME BUCKLES FASTENED OVER THE TOP OF IT WHILE THE AMERICAN MODEL DID WITHOUT. THE SEAT COVER PATTERN WAS THE SAME ON BOTH MODELS.UNDERNEATH THE SEAT, ATTACHED TO THE BASE, WAS FOUR LARGE DAMPER RUBBERS AND ONE SMALLER ONE. THESE RUBBERS RESTED ON THE TWO FRAME TUBES.ALSO ON THE SEAT BASE WAS A SQUARE SILVER DECAL SHOWING THE CORRECT ROUTING OF THE BATTERY VENT HOSE. THERE WAS TWO GLOSS BLACK HINGES WHICH BOLTED TO THE SEAT BASE BY FOUR 6MM ZINC PLATED BOLTS AND FASTENED THE SEAT TO THE FRAME BY TWO ZINC PLATED SEAT PINS AND SMALL R-CLIPS. ALSO ATTACHED TO THE SEAT BASE WAS A ZINC PLATED PLUNGER BOLT WHICH ACTED AS THE SEAT LOCK. THIS CONNECTED INTO A CATCH ASSEMBLY BOLTED TO THE FRAME BY TWO 6MM BOLTS. THIS ASSEMBLY WAS FINISHED IN GLOSS BLACK AND FASTENED TO IT BY TWO 5MM PAN HEAD SCREWS WAS THE KEY OPERATED SEAT LOCK ITSELF. ONCE THE KEY HAD BEEN TURNED, THE LOCK HELD IN POSITION THE CATCH ASSEMBLY, WHICH WOULD THEN NOT RELEASE THE PLUNGER. THE SMALL LEVER PROTRUDING OUT OF THE FRAME WAS FITTED WITH A SMALL RUBBER CAP, WHICH COULD THEN BE EASILY GRASPED. IT WAS A CRUDE AFFAIR BUT IT DID DO THE JOB.THE SEAT COVER WAS MADE FROM A BLACK VINYL MATERIAL AND COULD NOT BE BOUGHT SEPARATELY.ON UK MODELS AND SOME AMERICAN MODELS, A ZINC PLATED RESTRAINING BAR WAS FITTED TO THE FRAME, WHICH STOPPED THE SEAT FROM OPENING TO FAR AND HITTING THE RIGHT HAND SIDE PANEL. THIS BAR WAS FITTED WITH QUITE A STRONG RETURN SPRING AND SECURED WITH A SMALL R-CLIP.

CHAIN AND SPROCKETS:

THE Z1 WAS FITTED WITH AN EK630S-TG HEAVY DUTY CHAIN WITH 92 LINKS. THE CHAIN WAS ENDLESS AND REMOVAL OF THE SWING ARM WAS REQUIRED TO FIT A NEW ONE. THIS WAS THE BIGGEST CHAIN EVER FITTED TO A JAPANESE MOTORCYCLE AND IT WAS DESIGNED WITH THE Z1 IN MIND BY THE ENUMA COMPANY OF JAPAN. KAWASAKI HAD EXPECTED EXCESSIVE CHAIN WEAR ON THE Z1, SO THEY WENT FOR THE "BIGGEST IS BEST" APPROACH. THE FRONT SPROCKET WAS A 15 TOOTH ITEM AND WAS FASTENED TO THE GEARBOX OUTPUT SHAFT BY A 20MM NUT AND TAB WASHER.THE REAR SPROCKET, FINISHED IN SILVER, WAS A 35 TOOTH ITEM.

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THE CHAIN WAS PROTECTED BY A PLASTIC CHAIN GUARD, FINISHED IN BLACK, WHICH WAS FASTENED TO THE SWING ARM BY TWO 6MM ZINC PLATED BOLTS.THE CHAIN WAS ADJUSTED AT THE REAR OF THE SWING ARM BY TWO ZINC PLATED ADJUSTER PLATES. TWO ZINC PLATED 8MM BOLTS PUSHED AGAINST THE SWING ARM STOPPERS AND PULLED BACK THE REAR AXLE UNTIL CORRECT TENSION WAS OBTAINED. AN 8MM NUT THEN LOCKED THE ADJUSTER BOLT INTO PLACE. THE CORRECT ADJUSTMENT WAS 30-35 MM OF SLACK MEASURED BETWEEN THE TWO SPROCKETS.

ANOTHER FIRST ON THE Z1 WAS THE FITTING OF AN AUTOMATIC CHAIN OILER. UNDERNEATH THE LEFT HAND SIDE PANEL WAS A WHITE PLASTIC TANK WHICH HELD SAE 90 GEAR OIL. A RUBBER RETAINING STRAP HELD THIS TO A BRACKET. A DECAL WAS STUCK ONTO THE TANK STATING WHICH OIL WAS TO BE USED TO FILL IT UP WITH.ON TOP OF THE TANK WAS A BLACK, SCREW-ON, FILLER CAP AND A BLACK RUBBER DIPSTICK FOR CHECKING THE OIL LEVEL WHEN THE SIDE PANEL WAS FITTED. A BLACK VINYL OVERFLOW PIPE RAN UPWARDS FROM THE TOP OF THE TANK, OVER THE SIDE OF THE TOOLBOX AND DOWN TOWARDS THE SWING ARM. A SMALL FILTER SCREWED TO THE BOTTOM OF THE TANK AND FROM THIS LED A BLACK VINYL PIPE. THIS FED A SMALL PUMP IN THE RIGHT HAND ENGINE CASING WHICH IN TURN SPLASH FED THE FRONT SPROCKET WITH OIL. THE DRIVE FOR THIS PUMP CAME FROM A SMALL PIN SITUATED IN THE END OF THE GEARBOX OUTPUT SHAFT. THIS IN TURN LUBRICATED THE DRIVE CHAIN. THIS PROVED TO BE A VERY MESSY SYSTEM, BUT THE PUMP WAS ADJUSTABLE AND COULD BE REGULATED TO A MERE TRICKLE. OWNERS PREFERRED THIS SETTING BECAUSE THEIR PRIDE AND JOY LOOKED A LOT CLEANER. HOWEVER, THE PRICE TO PAY FOR THIS WAS EXTREME EXCESSIVE WEAR ON THE DRIVE CHAIN. SOME OWNERS WERE APPALLED TO FIND OUT THEY NEEDED TO REPLACE THE CHAIN WITHIN 5000 MILES! KAWASAKI CAME TO THE RESCUE AND REPLACED MOST CHAINS UNDER WARRANTY. IT BECAME APPARENT TO THEM HOWEVER THAT THEY WERE ON A LOSER, SO A REVISED INFORMATION STICKER WAS ATTACHED TO THE BIKES ON THE PRODUCTION LINE STATING THAT A REPLACEMENT CHAIN WOULD ONLY BE ALLOWED ON MACHINES THAT HAD COVERED UNDER 3000 MILES! ONLY ONE CHAIN PLUS THE ORIGINAL WAS ALLOWED PER BIKE.MOST OWNERS RAN THE OILER DRY AND RESORTED TO MANUALLY LUBRICATING THE CHAIN THEMSELVES.

IGNITION SYSTEM:

THE IGNITION SYSTEM ON THE Z1 WAS THE USUAL COIL AND BATTERY SET UP.INSIDE THE FRONT RIGHT HAND SIDE ENGINE CASE WAS A CENTRIFUGAL AUTOMATIC ADVANCER UNIT, WHICH WAS KEYED TO THE CRANKSHAFT BY A SMALL 4MM DOWEL PIN. THIS HAD A SINGLE LOBE CAM, WHICH OPENED EACH PAIR OF POINTS ONCE PER ENGINE REVOLUTION. THE ADVANCEMENT WAS MADE BY TWO SMALL SPRINGS, WHICH COULD NOT BE OBTAINED SEPARATELY. ON TOP OF THIS, SCREWED TO THE INNER ENGINE CASE BY THREE 5MM PAN HEAD SCREWS, WAS A BACKING PLATE WHICH HELD THE TWO SETS OF POINTS AND A PAIR OF CONDENSERS. A SMALL BLOCK OF FELT WAS ALSO ATTACHED TO THIS PLATE TO ASSIST IN LUBRICATING THE CAM. AN 8MM BOLT AND SPECIAL 17MM LOCKING WASHER THEN HELD EVERYTHING TOGETHER. THIS 17MM WASHER WAS MODIFIED ALMOST IMMEDIATELY BY KAWASAKI TO INCORPORATE A BUILT IN FLAT WASHER, GIVING IMPROVED CONNECTION TO THE AUTO ADVANCER.

THE POINTS FIRED A PAIR OF TWIN LEADED COILS WHICH WERE SITUATED UNDERNEATH THE FUEL TANK. THESE WERE MOUNTED TO BRACKETS ON THE FRAME BY TWO 6MM PAN HEAD SCREWS AND TIGHTENED UP BY 6MM NUTS. ORIGINALLY THE COILS WERE IN A "GREYISH" BAKELITE FINISH, BUT I HAVE SEEN SOME IN A BLACK FINISH. THIS WAS OBVIOUSLY AN INCONSISTENCY FROM THE SUPPLIER, THE TOYODENSO COMPANY OF JAPAN.TWO WIRES RAN FROM EACH COIL, ONE TO THE MAIN LOOM AND THE OTHER TO THE LOW TENSION LEAD, WHICH RAN FROM THE POINTS PLATE ASSEMBLY.THE HIGH TENSION LEADS WERE BONDED INTO THE BODIES OF THE COILS AND WERE NOT REMOVABLE. THE LEADS FOR 1+4 CYLINDERS WERE LONGER THAN THE LEADS FOR 2+3 CYLINDERS. UK MODELS WERE FITTED WITH METAL SHROUDED GREY PLASTIC PLUG CAPS WHILE AMERICAN MODELS HAD BLACK PLASTIC CAPS.FITTED TO EACH LEAD WAS A SMALL PLASTIC CLIP, WHICH WERE NUMBERED 1 TO 4. THIS ENSURED THE CORRECT LEAD WENT TO THE CORRECT CYLINDER.

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NGK B8ES SPARKING PLUGS WERE FITTED AS STANDARD, WHILE B9ES WERE RECOMMENDED FOR HIGH SPEED USE.

AIR CLEANER ASSEMBLY:THE AIR BOX FITTED TO THE Z1 WAS A ONE-PIECE RUBBER ITEM. INSERTED INTO THE TOP THROUGH AN OBLONG HOLE WAS A PAPER FILTER ELEMENT. THIS HAD A HANDLE ON THE TOP OF IT TO ASSIST IN REMOVAL. COVERING THIS HOLE WAS A BLACK PLASTIC GRILLED COVER, WHICH JUST PUSHED ONTO THE AIR BOX STOPPING ANY LARGE ITEMS ENTERING THE BOX. CONNECTED TO THE BOTTOM OF THE BOX WAS A RUBBER PIPE WHICH RAN TO THE TOP OF THE CRANKCASE BREATHER COVER. THIS PIPE WAS SECURED WITH A SMALL METAL WIRE CLIP. FOUR BLACK METAL CLAMPS SECURED THE INLET HOSES TO THE REAR OF THE CARBURETTORS ENSURING AN AIRTIGHT CONNECTION. A BLACK 5MM PAN HEAD SCREW TIGHTENED THESE CLAMPS.

EXHAUST SYSTEM:

THE SILENCER SYSTEM ON THE Z1 IS PERHAPS THE MOST VISUAL EXHAUST EVER FITTED TO A MOTORCYCLE. THE FOUR SEPARATE SILENCERS STAND OUT TO MAKE THE Z1 INSTANTLY RECOGNISABLE. EACH CHROME SILENCER WAS HELD TO THE CYLINDER HEAD PORT BY TWO ZINC PLATED HALF MOON COLLETS AND A CHROME STEEL FINNED CLAMP. THESE CLAMPS FITTED OVER TWO 6MM STUDS AND WERE SECURED WITH 6MM NUTS AND SPRING WASHERS. A COPPER CIRCULAR GASKET SEALED THE DOWN PIPE TO THE EXHAUST PORT ENSURING A GAS TIGHT FIT.THE DOWN PIPES WERE DOUBLE SKINNED TO REDUCE DISCOLORATION AND WERE WELDED TO THE MUFFLERS BEFORE THEY WERE CHROMED. THIS JOIN WAS JUST BELOW THE FRONT FOOTREST.EACH PAIR OF SILENCERS WAS CONNECTED AT THE REAR BY A SMALL RUBBER TUBE AND A ZINC PLATED CLAMP. A 6MM PAN HEAD SCREW TIGHTENED THIS CLAMP UP.A DAMPER RUBBER WAS FITTED TO EACH OF THE TWO LEFT HAND SILENCERS, ONE ON THE BOTTOM MUFFLER TO STOP THE MAIN STAND HITTING IT AND ONE ON THE UPPER MUFFLER FOR THE SIDE STAND.A CHROME 10 X 108MM BOLT RAN THROUGH EACH PAIR OF MUFFLERS AND THEN THROUGH A PAIR OF RUBBER COATED METAL BUSHES WHICH WERE SITUATED IN THE FRAME. A FLAT WASHER AND A 10MM LOCK NUT THEN TIGHTENED THE WHOLE LOT UP. THIS BOLT WAS MODIFIED VERY EARLY ON IN PRODUCTION AND REPLACED INSTEAD WITH A BOLT WITH A LARGE CHROME FLANGED HEAD.EACH SILENCER WAS FITTED AT THE REAR END WITH A BAFFLE SECURED WITH A 6MM BOLT. UK MODELS HAD A BAFFLE WITH A SMALL TUBE STICKING OUT OF THE END OF IT WHILE AMERICAN MODELS HAD BAFFLES WITH A BAR WELDED ACROSS THEM. THIS WAS TO ASSIST WITH REMOVAL.FURTHER DOWN INSIDE THE MUFFLER WAS A SERIES OF MORE BAFFLES, WHICH COULD NOT BE REMOVED. AT THE BOTTOM OF EACH SILENCER WAS A SMALL DRAIN HOLE WHERE WATER COULD ESCAPE. IT WAS VERY IMPORTANT TO KEEP THESE HOLES CLEAR OTHERWISE PREMATURE INTERNAL ROTTING WOULD OCCUR, SOMETIMES WITHIN MONTHS.THE WHOLE SYSTEM WAS VERY HEAVY AND MANY OWNERS REPLACED THEM WITH A NOISIER, LIGHTER, AND FASHIONABLE FOUR INTO ONE SYSTEM. THESE SOMETIMES INCREASED PERFORMANCE BUT MORE OFTEN THAN NOT DIDN'T.

CONTROL CABLES:

THE Z1 HAD A TOTAL OF FIVE CONTROL CABLES. ALL FINISHED IN BLACK.

A SPEEDOMETER CABLE RAN FROM THE GEARBOX ON THE FRONT WHEEL UP TO THE SPEEDOMETER HEAD. IT PASSED THROUGH THE CHROME METAL BRACKET, WHICH HELD THE FRONT BRAKE RUBBER HOSE PIPE ATTACHED TO THE LEFT HAND LOWER FORK LEG, AND A

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SMALL BLACK METAL CLAMP FASTENED TO THE BRAKE JUNCTION MOUNTING BOLT. BOTH ENDS OF THE CABLE HAD A SCREW FASTENING.

A TACHOMETER CABLE RAN FROM THE TACHOMETER DRIVE ON THE CYLINDER HEAD UP TO THE TACHOMETER HEAD. IT PASSED THROUGH A SMALL BLACK METAL CLAMP FASTENED TO THE BRAKE JUNCTION MOUNTING BOLT. BOTH ENDS HAD A SCREW FASTENING.

A CLUTCH CABLE RAN FROM THE CLUTCH RELEASE MECHANISM DOWN IN THE REAR LEFT HAND ENGINE CASE UP TO THE CLUTCH LEVER ON THE HANDLEBARS. THERE WAS A ZINC PLATED ADJUSTER HALF WAY UP THE CABLE AND BOTH ENDS HAD A NIPPLE ON THEM. A BLACK METAL CLAMP HELD THE CABLE CLOSE TO THE FRAME DOWN TUBE AWAY FROM THE EXHAUST. THERE WAS AN IDENTIFICATION NUMBER AT THE TOP OF THE CABLE. THIS NUMBER WAS 11-048.

THERE WERE TWO THROTTLE CABLES, ONE FOR OPENING THE CARBS AND ONE FOR CLOSING THEM. THERE WAS A CURVED CHROME ADJUSTER ON EACH CABLE AT THE TWIST GRIP END AND A STRAIGHT ZINC PLATED ADJUSTER AT THE CARB END. THEY PASSED THROUGH A CHROME CIRCULAR GUIDE FASTENED TO THE TOP RIGHT HAND YOKE MOUNTING BOLT.THERE WAS AN IDENTIFICATION NUMBER ON EACH CABLE AT THE TOP. ON THE OPEN CABLE THIS WAS 12-081 AND ON THE CLOSE CABLE, 12-087.

BODY WORK:

THE BODYWORK DESIGN OF THE Z1 HAS BECOME SOMETHING OF A LEGEND. MANY MODERN RETRO BIKES HAVE TRIED TO RE-CAPTURE THE FLOWING LINES OF THE Z1 INCLUDING KAWASAKI'S OWN ZEPHYR RANGE.THERE WERE TWO COLOUR OPTIONS FOR THE Z1. CANDY BROWN AND ORANGE AND CANDY GREEN AND YELLOW. MOST UK MODELS WERE IN THE BROWN OPTION WHILE MANY AMERICANS WENT FOR THE GREEN OPTION. THE TERM "CANDY" WAS A TERM GIVEN TO THE PAINTING PROCESS OF THE TIME. IT WAS ACTUALLY A MULTI COAT PROCESS USING METALLIC PAINTS AND COLOURED LACQUERS. THE FUEL TANK WAS A "TEAR-DROP" SHAPE PRESSED FROM STEEL. A CHROME FILLER CAP WAS FITTED ONTO THE TOP OF THE TANK AND OPENED BY A SMALL SPRING LOADED HOOK WHICH WAS DEPRESSED TO ALLOW THE CAP TO BE LIFTED UP. A BLACK FUEL TAP WAS SCREWED ONTO THE BOTTOM OF THE LEFT HAND SIDE OF THE TANK BY A LARGE NUT AND HAD THREE POSITION, ON, OFF AND RESERVE.THE TAP HAD A REMOVABLE SEDIMENT BOWL AND FILTER AT THE BOTTOM AND HAD TWO OUTLETS AT THE REAR WHICH FED FUEL TO THE CARBURETTORS. THERE WAS AN EMBLEM ON EACH SIDE OF THE TANK BARING THE NAME "KAWASAKI." THESE EMBLEMS WERE 155 MM LONG AND WERE SCREWED TO THE TANK BY TWO BLACK COUNTER SUNK 3MM PAN HEAD SCREWS. THE EMBLEMS WERE BLACK BASED WITH THE LETTERS FINISHED IN WHITE SURROUNDED BY CHROME.THE TANK WAS RUBBER MOUNTED BY TWO CIRCULAR RUBBERS AT THE FRONT, ONE ON EACH SIDE OF THE FRAME AND CUSHIONED UNDERNEATH AT THE REAR BY TWO HONEY-COMBED RUBBERS WHICH WRAPPED AROUND THE FRAME TUBES. A RUBBER STRAP THEN HELD THE TANK AT THE REAR HOLDING IT DOWN CLOSE TO THE FRAME.

THERE WAS A PLASTIC PANEL ON EACH SIDE FINISHED IN THE MAIN BODY COLOUR. THESE WERE SECURED TO THE FRAME BY LUGS THAT PUSHED INTO RUBBER GROMMETS, THREE ON EACH SIDE OF THE FRAME. THE LEFT SIDE COVERED THE CHAIN OILER TANK AND HAD A HOLE IN THE TOP TO ALLOW THE CHAIN OIL DIPSTICK TO PASS THROUGH. THERE WAS ALSO A HOLE TO ALLOW ACCESS TO THE SEAT LOCK.THE RIGHT HAND PANEL COVERED THE ELECTRICAL BASE PLATE.EACH PANEL HAD AN EMBLEM FITTED, WHICH WERE SECURED TO IT BY SMALL CLIPS AT THE REAR. THE EMBLEM PROUDLY ANNOUNCED "900 DOUBLE OVERHEAD CAMSHAFT." THE EMBLEM WAS BLACK BASED WITH THE "900" LEGEND IN WHITE SURROUNDED BY CHROME. THE REST OF THE LETTERS WERE IN CHROME ON A BLACK BACKGROUND.

A KAWASAKI TRADEMARK AT THE TIME WAS THE FITTING OF A TAIL FAIRING TO THEIR MODELS AND THE Z1 WAS NO EXCEPTION.

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THE PLASTIC TAILPIECE WAS RUBBER MOUNTED AND BOLTED TO THE FRAME BY FOUR 6MM ZINC PLATED BOLTS. TWO THROUGH THE TOP OF IT, UNDERNEATH THE SEAT AND TWO MORE UNDERNEATH THE FAIRING, ABOVE THE TAILLIGHT.THE BOLTS AT THE TOP ALSO HELD TWO GLOSS BLACK METAL HELMET HOOKS WHERE OWNERS COULD SECURE THEIR HELMET AFTER LOCKING DOWN THE SEAT.THERE WAS FOUR INFORMATION DECALS ON THE TAILPIECE, TWO FOR THE HELMET HOLDERS, ONE FOR ENGINE OIL AND ONE FOR REAR DRIVE CHAIN WARRANTY.INSIDE THE TAILPIECE THERE WAS A BLACK PLASTIC TRAY WHICH COULD BE USED TO HOLD IMPORTANT DOCUMENTS. THERE WAS A RUBBER HANDLE FITTED TO THIS TRAY TO ENABLE EASY REMOVAL. STUCK TO THE BASE OF THIS TRAY WAS A LARGE SILVER DECAL WITH SERVICE INFORMATION AND A WIRING DIAGRAM PRINTED ON IT.

THERE WAS NO COLOUR CODE PRODUCED FOR ANY OF THE COLOUR COMBINATIONS, ONLY A DESCRIPTION. CORRECTLY MATCHING THE ORIGINAL COLOUR IS VERY DIFFICULT. KAWASAKI THEMSELVES STRUGGLED AND MANY BIKES WERE INCONSISTENT IN THEIR FINISH. IT WAS QUITE RARE TO HAVE A BIKE WITH ALL COLOURED PARTS MATCHING AND INDEED, PINSTRIPES AND MARKINGS WERE NEVER THE SAME ON ANY TWO SAME BIKES.THERE ARE MANY COMPANIES OFFERING A PAINTING SERVICE THESE DAYS AND THE BEST I HAVE FOUND IS A COMPANY CALLED "DREAM MACHINE" IN NOTTINGHAM, HERE IN THE UK. THEIR QUALITY IS RENOWN ALL OVER THE WORLD AND THEY USE MODERN PAINTS AND TECHNIQUES TO ACHIEVE A "BETTER THAN NEW" FINISH.THE MOST POPULAR COLOUR CHOICE BY FAR IS THE BROWN AND ORANGE OPTION, OFTEN REFERRED TO AS A "JAFFA CAKE." HOWEVER THE GREEN AND YELLOW IS WORTH CONSIDERING IF ONLY TO BE DIFFERENT.KAWASAKI DID OFFER A SMALL POT OF PAINT, IN A 1/12 LITRE TIN, AS A TOUCH UP FOR THE Z1 BUT IT WAS VERY AWKWARD TO USE. THE PART NUMBER FOR THESE WERE, BROWN 56019-108-96 AND GREEN 56019-108-97.

TOOLKIT AND HANDBOOK:

THE Z1 WAS SUPPLIED WITH A 56 PAGE OWNERS HANDBOOK, PART NUMBER 99997-800. THIS COVERED OPERATIONAL INSTRUCTIONS AND BASIC MAINTENANCE PROCEDURES. ALSO INCLUDED IN IT WAS A FULL COLOUR WIRING DIAGRAM.THE COVER OF THE HANDBOOK WAS WHITE WITH BLACK AND GOLD WRITING.

THE TOOLKIT SUPPLIED WAS ADEQUATE FOR BASIC MAINTENANCE AND WAS CONTAINED IN A BLACK VINYL POUCH. IT WAS LOCATED IN THE TOOLBOX UNDERNEATH THE SEAT. THERE WAS SIXTEEN DIFFERENT TOOLS SUPPLIED INCLUDING A SELECTION OF OPEN-ENDED SPANNERS, SCREWDRIVERS, A SPARK PLUG WRENCH, PLIERS, SHOCK ABSORBERS ADJUSTING TOOL, ALLEN KEY, AND A FEELER GAUGE.

ALSO AVAILABLE FROM KAWASAKI WAS A WORKSHOP MANUAL. THE PART NUMBER FOR THIS WAS 99997-700. THIS MANUAL WAS UPDATED EACH YEAR UP TO AND INCLUDING THE Z900-A4 OF 1976. UNFORTUNATELY THE MANUAL IS NOW NO LONGER AVAILABLE FROM KAWASAKI.

CHAPTER THREE

ENGINE, GEARBOX AND CARBURETTOR: STARTING ENGINE NO: Z1E-000001-Z1E-020000

THE HEART OF THE Z1 WAS THE ENGINE. NEVER BEFORE HAD ANYONE SEEN AN ENGINE AS TOUGH AS THIS. IT TRULY DESERVED THE TITLE GIVEN TO IT "BULLET PROOF." IF THE FRAME AND SUSPENSION WAS CONSIDERED A COMPROMISE, THEN THE ENGINE MORE THAN MADE AMENDS.

CRANKCASES:THE CRANKCASES WERE TYPICAL JAPANESE IN THEIR DESIGN BEING SPLIT HORIZONTALLY. THEY WERE MATCHED TOGETHER AS A PAIR AND WERE FINISHED IN A SATIN BLACK PAINT.

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THERE WAS A FLAT BOSS ON THE TOP CASE WHERE THE ENGINE NUMBER WAS STAMPED. ALL Z1 ENGINES BEGAN WITH THE PREFIX Z1E. THE "E" STOOD FOR ENGINE. ALSO FITTED TO THE TOP CASE WAS THE OIL FILLER CAP. THIS CAP WAS A SCREW FITTING AND WAS SEALED WITH AN O`RING. THE TYPE OF OIL RECOMMENDED, SAE 10W-40, WAS EMBOSSED ONTO THE TOP OF THE CAP.3.7 LITRES OF OIL WERE POURED INTO THIS HOLE AND RAN DOWN OVER THE CLUTCH AND DIRECTLY INTO THE SUMP.THE BEARING HOUSINGS FOR THE GEARBOX AND CRANKSHAFT WERE ALL MACHINED WITH THE CASES ASSEMBLED AND A SERIES OF PINS AND HALF RINGS LOCATED THE RELEVANT BEARINGS BOTH RADIALLY AND AXIALLY.THE CASES WERE HELD TOGETHER BY TWENTY-TWO 6MM BOLTS AND EIGHT 8MM BOLTS. THE LARGER 8MM BOLTS WERE SITUATED OVER THE CRANKSHAFT MAIN BEARINGS. NO GASKET WAS USED BETWEEN THE TWO HALVES BUT KAWASAKI DID RECOMMENDED THE USE OF LIQUID GASKET CEMENT.THERE WAS A SMALL O`RING FITTED BETWEEN THE TWO HALVES, SEALING THE OIL PASSAGE, BUT THIS WAS NOT MENTIONED IN THE PARTS BOOK. THE PART NUMBER FOR THIS O`RING IS 92055-048. TWELVE 10MM STUDS SCREWED INTO THE TOP CRANKCASE. ON TO THESE FITTED THE CYLINDER HEAD AND BARRELS. THE CASES WERE FINNED AT THE FRONT TO ASSIST IN THE COOLING OF THE ENGINE.

CRANKSHAFT:THE CRANKSHAFT ASSEMBLY WAS AN ALL CAGED ROLLER BEARING AFFAIR WITH A TOTAL OF SIX MAIN BEARINGS. THE CENTRE TWO BEARINGS WERE SUPPORTED BY THE MAIN BEARING CAP, WHICH WAS LINE BORED AND MATCHED WITH THE CRANKCASES. THIS CAP WAS BOLTED TO THE TOP CRANKCASE BY FOUR 8MM BOLTS.THE CRANK WAS PRESSED TOGETHER WITH THE MAIN SHAFTS FORGED WITH THE WEBS AND SHAPED TO PROVIDE A BALANCING EFFECT.NONE OF THE MAIN BEARINGS WERE AVAILABLE AS A SEPARATE PART SO IN THE VERY UNLIKELY EVENT OF FAILURE THE WHOLE OF THE CRANKSHAFT HAD TO BE REPLACED. THE MAIN BEARINGS WERE ALL FITTED INTO HOUSINGS AND EACH OF THE SIX WERE FIXED BY A PIN TO ENSURE ALIGNMENT OF THE OIL HOLES.FOUR ONE-PIECE CON RODS WERE USED WITH PLAIN LITTLE ENDS.THERE WAS A TAPERED SHAFT ON THE LEFT HAND SIDE OF THE CRANK, THREADED WITH A 8MM HOLE, WHERE THE ALTERNATOR ROTOR FITTED. THERE WAS A SMALL SLIT MACHINED INTO THE TAPER FOR FIGMENT OF A WOODRUFF KEY.THE RIGHT HAND SIDE OF THE CRANK WAS THREADED WITH A 8MM HOLE AND DRILLED WITH A SMALL 4MM HOLE WHERE THE TIMING ADVANCER PEGGED INTO.THREE GEARS WERE CUT INTO THE CRANK. IN THE CENTRE WAS THE GEAR DRIVE FOR THE CAM CHAIN AND MACHINED INTO THE INNER WEB OF THE RIGHT HAND SIDE WAS THE PRIMARY DRIVE. ANOTHER GEAR WAS MACHINED ON THE LEFT SIDE TO DRIVE THE OIL PUMP.

PISTONS AND RINGS:FOUR 66MM DOMED PISTONS, MADE BY THE 'ART' COMPANY, WERE HELD TO THE CON RODS BY GUDGEON PINS AND SECURED BY TWO CIRCLIPS ON EACH PISTON. EACH PISTON HAD AN ARROW STAMPED ON THE TOP OF IT TO MAKE SURE IT WAS FITTED FACING THE RIGHT WAY. TWO OVERSIZES WERE AVAILABLE, 0.5MM AND 1.00MM. THE PISTONS GIVE A COMPRESSION RATIO OF 8.5:1. THREE PISTON RINGS WERE FITTED TO EACH PISTON, ONE SCRAPER AND TWO COMPRESSION. THE CENTRE RING WAS MANUFACTURED WITH A REBATE ON THE INSIDE OF IT. TWO OVERSIZES OF 0.5MM AND 1.00MM WERE AVAILABLE.

CYLINDER BARRELS:

THE CYLINDER BARRELS WERE OF LIGHT ALLOY CONSTRUCTION AND FINISHED IN SATIN BLACK. FOUR IRON SLEEVES WERE COLD PRESSED INTO THEM. BORE AND STROKE WAS EQUAL AT 66MM GIVING A DISPLACEMENT OF 903CC.THE BARRELS WERE HEAVILY FINNED TO ASSIST IN COOLING. THE OUTSIDE EDGE OF THE FINS WERE POLISHED AT EACH END AND CONTINUED POLISHED AROUND THE FRONT.

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THE LINERS PROTRUDED FROM THE BASE OF THE BLOCK AND LOCATED INTO THE TOP CRANKCASE TO ASSIST IN SUPPORTING THE PISTONS. FITTED TO THE BOTTOM OF EACH LINER WAS A 73MM O`RING. A SERIES OF SMALL ROUND RUBBER DAMPERS WERE ALSO INSERTED INTO THE BASE OF THE BARRELS. THESE EIGHT RUBBERS WERE NOT SHOWN IN THE PARTS BOOK, BUT THEY WERE AVAILABLE UNDER THE PART NUMBER 92074-030.HOLLOW DOWEL PINS WERE FITTED OVER THE TWO FRONT END CYLINDER STUDS AND A PAPER GASKET SAT ON TOP OF THE CRANKCASES. THE BLOCK WAS THEN FITTED OVER THE TWELVE STUDS.THE CYLINDER HAD A TUNNEL CAST INTO THE CENTRE OF IT WHERE THE CAM CHAIN RAN AND ON EACH END THERE WAS TWO 6MM THREADED HOLES. TWO MORE HOLLOW DOWELS SAT IN THESE HOLES.THERE WAS A SQUARE HOLE IN THE REAR OF THE BLOCK WHERE THE CAM CHAIN TENSIONER BODY FITTED. ABOVE AND BELOW THIS HOLE WAS A 6MM THREADED HOLE.THE FRONT BOTTOM LEFT OF THE CYLINDER WAS STAMPED WITH THE LEGEND "903CC" TO HELP IDENTIFY IT.ORIGINALLY THE Z1 WAS FITTED WITH A SINGLE ONE-PIECE HEAD GASKET BUT IT WAS SOON DISCOVERED THAT THIS CAUSED EXCESSIVE OIL LEAKS FROM AROUND THE CAM CHAIN TUNNEL AREA. KAWASAKI MODIFIED THE CYLINDERS FROM ENGINE NUMBER Z1E-14319 ONWARDS. THIS MODIFICATION CONSISTED OF A GROVE MACHINED AROUND THE TOP OF THE CAM CHAIN TUNNEL WHICH WAS THEN FITTED WITH A SHAPED O`RING. THE PART NUMBER FOR THIS O`RING WAS 92055-062. A TWO PIECE HEAD GASKET WAS THEN FITTED, BOTH HALVES BEING THE SAME. THE PART NUMBER OF THESE GASKETS WAS 11004-066. THIS SEEMED TO CURE THE PROBLEM.

CYLINDER HEAD:

THE CYLINDER HEAD WAS OF A LIGHT ALLOY CONSTRUCTION AND FINISHED IN BLACK. IT WAS WELL FINNED AND LIKE THE CYLINDERS, THE OUTER FINS WERE POLISHED. THE POLISHING STARTED AT THE SIDES AND EXTENDED TO THE FRONT.EIGHT 6MM STUDS SURROUNDED THE FOUR EXHAUST PORTS TO WHICH THE EXHAUST COLLARS FITTED. EIGHT VALVE SEATS WERE CAST INTO THE HEAD AND WERE OF A VERY HARD MATERIAL TO ENABLE THE USE OF LEAD FREE FUEL. THE EIGHT VALVES MOVED IN BRONZE GUIDES THAT WERE PRESSED INTO THE HEAD AND SECURED BY SMALL CIRCLIPS. THESE GUIDES PROVED TO BE TO SOFT FOR THE JOB AND WERE ONE OF THE FEW MISTAKES KAWASAKI ENGINEERS MADE. THEY WERE LATER MODIFIED TO A CAST IRON ITEM.A SMALL OIL SEAL WAS FITTED TO THE TOP OF EACH GUIDE, WHICH STOPPED ANY OIL SEEPING DOWN THE VALVE STEM. EACH VALVE HAD AN INNER AND OUTER SPRING, WHICH SAT ON A STEEL SEAT AROUND THE GUIDE. A COLLAR AND TWO COLLETS RETAINED THE SPRINGS. ON THE TOP OF EACH VALVE ASSEMBLE WAS A BUCKET WHICH HELD THE VALVE CLEARANCE ADJUSTING SHIM. AT THE FRONT OF THE HEAD, JUST ABOVE NUMBER THREE EXHAUST PORT WAS A HOLE, WHICH HELD THE TACHOMETER DRIVE GEAR. THE GEAR WAS HOUSED IN A THREADED HOLDER WHICH CONTAINED A SMALL OIL SEAL AND O`RING AND WAS SECURED TO THE HEAD BY A 6MM PAN HEAD SCREW. THE REV COUNTER CABLE SCREWED ONTO THIS HOUSING.FASTENED TO THE REAR OF THE HEAD WERE THE FOUR CARBURETTOR INLET RUBBERS. THESE WERE MADE FROM A HARD RUBBER COMPOSITE AND SECURED TO THE HEAD BY EIGHT 6MM PAN HEAD SCREWS, TWO FOR EACH RUBBER. FITTED TO THESE RUBBERS WERE FOUR BLACK METAL CLAMPS THAT WERE USED TO TIGHTEN THE RUBBERS TO THE CARBS. EACH CLAMP USED A BLACK 5MM PAN HEAD SCREW.BUILT INTO THE HEAD WERE FOUR NIPPLES, ONE FOR EACH CYLINDER. THESE WERE LOCATED INTO EACH CYLINDERS INLET TRACK AND USED FOR TAKE OFF POINTS TO BALANCE THE CARBS. WHEN NOT IN USE THEY WERE BLANKED OFF WITH A SMALL RUBBER PLUG.THIS PROVED TO BE TROUBLESOME AND KAWASAKI MODIFIED THE CYLINDER HEAD FROM ENGINE NUMBER Z1E-2201 ONWARDS. THE MODIFIED HEAD NO LONGER HAD THE NIPPLES IN THEM, BUT INSTEAD MODIFIED INLET RUBBERS WERE SUPPLIED WITH THE NIPPLES BUILT INTO THEM. THE PART NUMBER FOR THE MODIFIED HEAD WAS 11002-012 AND THE MODIFIED RUBBERS WERE 16065-022 FOR THE RH AND 16065-023 FOR THE LH. TWO OF EACH WAS

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REQUIRED. THESE WERE HANDED DUE TO THE FACT THAT THE NIPPLES STUCK OUT AT AN ANGLE TO ASSIST THE FIGMENT OF THE CARB VACUUM BALANCE PIPES.TWO CAMSHAFTS SAT ON THE TOP OF THE CYLINDER HEAD. THESE WERE OF A HOLLOW DESIGN AND WERE HELD BY FOUR CAMSHAFT CAPS THAT WERE NUMBERED ONE TO FOUR AND LINE BORED WITH THE CYLINDER HEAD. THESE CAPS WERE NOT AVAILABLE AS A SEPARATE PART AND IF BROKEN A COMPLETE NEW HEAD WAS REQUIRED. EACH CAP WAS SECURED BY FOUR 6MM BOLTS AND LOCATED BY TWO SMALL DOWEL PINS. AN ARROW CAST INTO THE TOP OF EACH CAP ENSURED THAT THE CAP WAS CORRECTLY FITTED. FOUR PAIRS OF SPLIT PLAIN BEARINGS SURROUNDED THE CAMS, TWO IN EACH CAP AND TWO SITTING IN THE HEAD DIRECTLY OPPOSITE TO THEM. BOLTED TO EACH CAM BY THREE 6MM BOLTS WAS A CAMSHAFT SPROCKET. STAMPED ONTO THESE WERE THE CAMSHAFT TIMING MARKS. THE EXHAUST CAM WAS ALSO MACHINED WITH A SKEW GEAR, WHICH DROVE THE TACHOMETER DRIVE GEAR.THE CAM LOBE RAN DIRECTLY ONTO THE SHIMS AND ADJUSTMENT WAS MADE BY CHANGING THESE SHIMS TO OBTAIN THE CORRECT CLEARANCE. THE SHIMS WERE AVAILABLE IN SIZES FROM 2.00 TO 3.20 MM IN INCREMENTS OF 0.05MM. A SPECIAL TOOL, PART NUMBER 57001-113, WAS AVAILABLE TO ASSIST IN CHANGING THESE SHIMS.THE HEAD WAS FITTED OVER THE TWELVE CRANKCASE STUDS AND SECURED BY TWELVE 10MM CHROME TOP HAT DOMED NUTS. UNDER THESE NUT WAS A 10MM COPPER WASHER WHICH ACTED AS A GASKET. ORIGINALLY THESE NUTS WERE 10.5MM HIGH BUT A PROBLEM WAS EXPERIENCED WITH OIL SEEPAGE FROM THE CYLINDER BASE GASKET AND IT WAS DECIDED TO INCREASE THE HEIGHT OF THE NUT TO 13MM SO THAT EXTRA TORQUE COULD BE APPLIED TO THEM. THE MODIFIED PART NUMBER FOR THESE NUTS WAS 92015-070.EITHER THE ONE PIECE HEAD GASKET OR LATER BY THE TWO PIECE GASKET AND THE SHAPED O`RING SEALED THE HEAD TO THE CYLINDER BARREL.A CHROME 6MM BOLT ON EACH END OF THE HEAD BOLTED THROUGH TO THE CYLINDER BARREL DOWN THROUGH THE DOWEL PINS AND COMPLETED THE FASTENING PROCEDURE. FOUR SPARKING PLUGS WERE SCREWED INTO THE HEAD INCLINED OUTWARDS. THE FINNING PATTERN OF THE CYLINDER HEAD WAS SUCH THAT AIR FLOWED PAST THE PLUGS INWARDS AND HELPED TO COOL ALL FOUR OF THEM.AT THE END OF EACH CAMBOX WAS A HALF CIRCULAR CUT OUT WHERE THE HEAD HAD BEEN LINE BORED FOR THE CAMSHAFT CAPS. TO BLOCK THESE HOLES OFF THERE WERE FOUR HALF MOON RUBBER BUNGS FITTED, TWO ON EACH END.A "H" SHAPED GASKET WAS THEN FITTED FOLLOWED BY THE CAM COVER.THIS COVER WAS ALSO FINISHED IN BLACK BUT THE FOUR ROUNDED ENDS WERE HIGHLY POLISHED.SIXTEEN CHROME 6MM BOLTS SECURED THE COVER TO THE CYLINDER HEAD AND FASTENED TO FOUR OF THEM WERE RUBBER COATED METAL CLAMPS THAT WERE USED TO HOLD THE FOUR HIGH TENSION LEADS AWAY FROM THE HOT CYLINDER HEAD.

CAMCHAIN AND TENSIONER:

A SINGLE ENDLESS CHAIN DROVE THE CAMSHAFTS FROM THE GEAR CUT INTO THE CENTRE OF THE CRANKSHAFT. THIS CHAIN WAS 219T X 122 LINKS.THE FIRST TENSIONER WAS A RUBBER ROLLER LOCATED IN THE TOP OF THE CRANKCASES WITH THE CHAIN PASSING EITHER SIDE OF IT. IT ROTATED ON A SMALL METAL SHAFT AND WAS DAMPENED BY TWO SMALL BLOCKS OF RUBBER.AS THE CHAIN PASSED THROUGH THE CYLINDER BARRELS IT WAS TENSIONED AT THE FRONT BY A SMALL RUBBER SLIPPER BLADE WHICH WAS SECURED TO THE BLOCK BY A 6MM PAN HEAD SCREW. TENSION WAS OBTAINED AT THE REAR BY ANOTHER RUBBER ROLLER THAT WAS ENCASED IN A METAL CAGE. THE CAM CHAIN TENSIONER PLUNGER PUSHED AGAINST THIS CAGE TO ENSURE CONSTANT TENSION. THIS PLUNGER WAS PART OF THE TENSIONER ASSEMBLE WHICH BOLTED TO THE BACK OF THE BLOCK BY TWO 6MM BOLTS. ENCLOSED WITH THE ASSEMBLE WAS AN ALLOY BODY WHICH HELD A LARGE SPRING AND THE PLUNGER ITSELF. ADJUSTMENT WAS MADE BY A 6MM BOLT AND LOCK NUT WHICH WHEN LOOSENED ALLOWED THE PLUNGER TO MOVE FORWARD AND DO ITS JOB. AFTER ADJUSTMENT THE BOLT AND NUT WAS TIGHTENED UP AGAIN. THE PLUNGER WAS A METAL ROD WITH A RUBBER COATED METAL PAD AT THE END.

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SITTING ON THE TOP OF THE CYLINDER BLOCK WERE TWO METAL TOOTHED IDLER GEARS. THE CAMCHAIN ENGAGED WITH THESE MAKING SURE THE CHAIN RAN TRUE. THESE IDLERS RAN IN A NEEDLE ROLLER BEARING AND ROTATED ON SMALL METAL SHAFTS THAT WERE EACH DAMPED BY TWO SMALL BLOCKS OF RUBBER. THE REAR IDLER ALSO HELD THE METAL CAGE WITH THE RUBBER ROLLER IN IT.THE CHAIN THEN RAN OVER BOTH THE CAMSHAFTS AND THE FINAL TENSIONER WAS ANOTHER METAL TOOTHED IDLER GEAR, THIS TIME ENCLOSED IN A METAL CAGE. THIS WAS DAMPED BY FOUR OBLONG RUBBER PADS, TWO ON EACH SIDE, AND THEN BOLTED TO THE TOP OF THE CYLINDER HEAD BETWEEN THE TWO CAMS BY FOUR 6MM BOLTS. VIBRATION AT CERTAIN REVS WAS SOMETIMES TRACED TO THE IDLER SHAFTS AND KAWASAKI MODIFIED THESE SHAFTS, MAKING THE GROVES 0.5MM DEEPER. THE NEW PART NUMBER FOR THESE SHAFTS WAS 12052-005 AND THEY WERE TO BE FITTED ALONG WITH MODIFIED BLOCK RUBBERS, PART NUMBER 92075-232. MODIFIED PARTS WERE FITTED TO THE PRODUCTION LINE FROM ENGINE NUMBER Z1E-17089 ONWARDS.THIS SYSTEM WHILE ADEQUATE, PROVED TO BE ANOTHER WEAK SPOT AND REPLACEMENT OF THE CHAIN AND VARIOUS TENSIONERS MEANT THE COMPLETE STRIP DOWN OF THE ENGINE. A SOFT RIVET LINK SPLIT CHAIN WAS THE ONLY CHEAP OPTION BUT THIS DID NOT REPLACE THE WORN OUT TENSIONERS. IT MERELY PROLONGED THE AGONY.

GEARBOX:

THE Z1 WAS FITTED WITH A FIVE SPEED RETURN SHIFT GEARBOX LOCATED IN THE REAR OF THE CRANKCASES.A LARGE ROLLER BEARING AT ONE END AND A SMALLER NEEDLE ROLLER BEARING AT THE OTHER END SUPPORTED EACH GEAR SHAFT IN THE CRANKCASES. BUSHES SURROUNDED THE NEEDLE ROLLER BEARINGS AND THESE WERE THEN LOCATED BY PINS TO THE CRANKCASES.THE FIVE GEARS WERE ARRANGED IN THE ORDER OF 2, 5, 3, 4, 1 STARTING FROM THE LEFT. THE GEARS WERE SEPARATED BY A SERIES OF THRUST WASHERS AND CIRCLIPS. THE CLUTCH WAS CONNECTED TO THE END OF THE INPUT SHAFT WHILE THE FRONT ENGINE SPROCKET WAS CONNECTED TO THE END OF THE OUTPUT SHAFT.NEUTRAL WAS LOCATED BETWEEN FIRST AND SECOND GEAR AND WAS EASY TO FIND DUE TO A POSITIVE NEUTRAL FINDING SYSTEM. THIS COMPRISED OF THREE SMALL BALL BEARINGS SET INSIDE FOURTH GEAR. WHEN THE OUTPUT SHAFT WAS TURNING THEY FLEW OUT UNDER CENTRIFUGAL FORCE AND ALLOWED THE GEAR TO SLIDE SIDEWAYS FOR SELECTION BUT WHEN AT A STANDSTILL, SUCH AS AT TRAFFIC LIGHTS, AT LEAST ONE BALL WOULD DROP INTO A SLOT IN THE SHAFT AND PREVENT THE GEARBOX FROM MOVING INTO SECOND GEAR. SIMPLE BUT EFFECTIVE.SELECTION OF THE GEARS WAS MADE BY THREE SELECTOR FORKS. ONE OF THESE RAN ON THE SELECTOR DRUM WHILE THE OTHER TWO BOTH IDENTICAL FORKS RAN ON THEIR OWN SHAFT. ALL THREE FORKS ENGAGED, BY PINS, WITH GROOVES IN THE SELECTOR DRUM ENABLING SELECTION OF ALL FIVE GEARS.THE SELECTOR DRUM EMERGED ON THE LEFT HAND SIDE OF THE CRANKCASES WITH A SIX PIN CIRCULAR PLATE. A RAISED CONTACT ON THIS PLATE EARTHED OUT A NEUTRAL POSITIONING SWITCH WHICH IN TURN ACTIVATED THE GREEN WARNING LIGHT ON THE IDIOT LIGHT CONSOLE.A SYSTEM OF SCISSORS LIKE FORKS AND PLATES WERE ATTACHED TO A SPLINED GEAR CHANGE SHAFT WHICH PROTRUDED THROUGH THE BACK LEFT HAND OUTER ENGINE CASE. A CHROME GEAR CHANGE PEDAL WAS BOLTED TO THIS SHAFT BY A CHROME 6MM BOLT. A SMALL RUBBER THEN PUSHED ONTO THE END OF THE LEVER.A STRONG SPRING ATTACHED TO THE SHAFT ENSURED A POSITIVE RETURN WHEN EACH GEAR HAD BEEN SELECTED. SELECTING FIRST GEAR WAS ALWAYS ACCOMPANIED BY A LOUD CLONKING SOUND WHICH BECAME A KAWASAKI TRADITION BUT THE GEARBOX IN GENERAL WAS EXCELLENT.

CLUTCH:

THE CLUTCH ON THE Z1 WAS A MULTI PLATE UNIT CONSISTING OF EIGHT FRICTION PLATES AND SEVEN STEEL PLATES. A 20MM LOCKING NUT ATTACHED THE CLUTCH BASKET TO THE INPUT SHAFT.

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IN THE CENTRE OF THE BASKET WAS A LARGE NEEDLE ROLLER BEARING, WHICH RAN IN A PLAIN BUSH. EXCESSIVE WEAR WAS NOTICED IN THIS BUSH AND KAWASAKI MODIFIED IT ALMOST IMMEDIATELY. THE NEW PART NUMBER FOR THIS BUSH WAS 92028-135.THE BACK OF THE BASKET WAS DAMPED BY A SERIES OF COILED SPRINGS, WHICH NORMALLY WERE NOT REMOVABLE. BUILT INTO THIS BASIC CUSH DRIVE WAS A LARGE STRAIGHT CUT GEAR WHICH MESHED TO THE PRIMARY DRIVE GEAR ON THE CRANKSHAFT TO PROVIDE DRIVE TO THE GEARBOX. INSIDE THE CLUTCH BASKET WAS AN ALUMINIUM HUB, WHICH HELD THE VARIOUS PLATES IN PLACE.THIS HUB WAS SPLINED IN THE MIDDLE AND FIXED DIRECTLY ONTO THE INPUT SHAFT. SANDWICHED BETWEEN THE HUB AND THE BASKET WAS A THRUST WASHER. THE HUB HAD FIVE FINGER LIKE 6MM THREADED PROJECTIONS TO WHICH THE FIVE CLUTCH SPRINGS WERE SECURED TO.THE OUTER CLUTCH PRESSURE PLATE WAS FITTED TO THE END OF THE ASSEMBLY AND TIGHTENED UP BY FIVE 6MM BOLTS AND WASHERS.RUNNING THROUGH THE INPUT SHAFT FROM LEFT TO RIGHT, WAS A LONG METAL PUSH ROD, WHICH PUSHED AGAINST A 3/8 BALL BEARING. THIS IN TURN PUSHED AGAINST A MUSHROOM TYPE PUSHER AND MADE CONTACT WITH THE INSIDE OF THE OUTER PRESSURE PLATE.ADJUSTMENT WAS MADE BY A TWO PIECE RELEASE MECHANISM THAT WAS SCREWED INTO THE OUTSIDE REAR LEFT HAND ENGINE CASE BY TWO 6MM PAN HEAD SCREWS. THIS WAS A WORM TYPE ASSEMBLY WITH AN INTERNAL 8MM-SLOTTED SCREW ADJUSTER. CONNECTED TO THE INNER RELEASE PIECE WAS AN ARM TO WHICH THE CLUTCH CABLE ATTACHED. BETWEEN THE ARM AND THE CABLE WAS A SHORT COILED SPRING, WHICH PLACED A SMALL AMOUNT OF TENSION ON THE CABLE.A SMALL COTTER PIN FITTED THROUGH THIS ARM, ENSURING THAT THE CABLE DID NOT COME OUT.

KICK-STARTER:THE Z1 WAS FITTED WITH A KICK-START AS WELL AS THE ELECTRIC STARTER. THE KICK-STARTER SHAFT RAN THROUGH THE REAR RIGHT HAND SIDE OF THE CRANKCASES AND WAS MESHED WITH FIRST GEAR ON THE OUTPUT SHAFT BY A SIMPLE RATCHET GEAR. ON A DOWNWARD STROKE THE RATCHET GEAR TURNED THE GEARBOX AND THEN THE CLUTCH AND THUS THE CRANKSHAFT.A METAL STOP PLATE, SECURED TO THE CRANKCASES, PULLED THE RATCHET OUT OF MESH WHEN THE PEDAL WAS RETURNED TO ALLOW THE GEAR TO RUN FREE.A LARGE COILED SPRING WAS USED TO PROVIDE A RETURN FOR THE PEDAL.THE PEDAL ITSELF WAS FITTED OVER THE SPLINED SHAFT AND SECURED WITH ZINC PLATED 14MM BOLT. THE LEVER PIVOTED ON A STEM FROM THE KICK-START BOSS AND WAS HELD TO THIS STEM BY A 10MM CIRCLIP AND WASHER. A SMALL SPRING LOADED BALL BEARING SAT INTO AN INDENT ON THE BOSS TO ASSIST IN POSITIONING. THE PEDAL WAS CHROMED AND A RIBBED RUBBER PROTECTED IT FROM YOUR FOOT.ORIGINALLY IT HAD QUITE A PROMINENT BEND IN IT, ABOUT A THIRD OF THE WAY UP, BUT THIS WAS MODIFIED ON LATER MODELS TO A STRAIGHTER DESIGN.THE KICK-START WAS RARELY REQUIRED, BUT IF NEED BE, IT COULD TURN THE ENGINE OVER VERY EASILY. IN FACT, IT WAS THAT EASY YOU COULD TURN IT OVER WITH YOUR HAND!

LUBRICATION SYSTEM:

THE LUBRICATION SYSTEM WAS A WET SUMP DESIGN AND A SINGLE OIL PUMP SAW TO THE NEEDS OF THE ENGINE, GEARBOX, AND CLUTCH.THE OIL PUMP WAS DIRECTLY DRIVEN BY THE TOOTHED GEAR ON THE CRANKSHAFT AND BOLTED INTO THE INSIDE BOTTOM OF THE CRANKCASES BY THREE 6MM BOLTS, USING TWO SMALL DOWEL PINS ON TWO OF THE BOLTS.ONE O`RING WAS FITTED WHERE OIL ENTERED THE PUMP FROM THE OIL PASSAGE IN THE CRANKCASES.ATTACHED UNDERNEATH THE PUMP, BY THREE 5MM PAN HEAD SCREWS, WAS A LARGE GAUZE FILTER. FROM HERE THE OIL WENT INTO THE OIL FILTER ELEMENT.

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SCREWED INTO THE SIDE OF THE OIL FILTER HOUSING WAS A BY-PASS VALVE IN CASE THE FILTER ELEMENT GOT BLOCKED.FROM THE OIL FILTER THE OIL WENT ALONG THE MAIN DISTRIBUTION TUNNEL, ALONG THE BACK OF THE UPPER CRANKCASE. A SMALL REMOVABLE PLUG AND O`RING BLOCKED OFF THIS TUNNEL ON THE RIGHT HAND SIDE OF THE CRANKCASES. THIS PLUG COULD BE SCREWED OUT OF THE CASES AND AN OIL PRESSURE GAUGE, A KAWASAKI SPECIAL TOOL, COULD BE FITTED.FROM THIS PASSAGE THE OIL COULD THEN TAKE THREE PATHS. FIRSTLY, TO THE MAIN BEARINGS ON THE CRANKSHAFT, THE BIG END BEARINGS AND THE STARTER CLUTCH ASSEMBLY. THIS OIL THEN SPLASH FED THE CON RODS, LITTLE ENDS, AND THE CYLINDER BORES.SECONDLY, THE OIL FED THROUGH THE REAR CRANKCASE STUDS, UP THROUGH THE CYLINDER BARRELS AND UP INTO THE CYLINDER HEAD. FROM HERE IT LUBRICATED THE CAMSHAFT BEARINGS AND SPLASH FED THE CAMS AND VALVE LIFTERS. IT THEN DRAINED DOWN THE CAM CHAIN TUNNEL BACK TO THE SUMP.THIRDLY, THE OIL WAS FED TO THE GEARBOX BEARINGS AND THEN SPLASH FED THE REST OF THE TRANSMISSION AND CLUTCH BEFORE RETURNING TO THE SUMP.TAKING A FEED FROM THE MAIN OIL PASSAGE WAS AN ALLOY HOUSING WHICH HELD THE OIL PRESSURE SWITCH. THIS HOUSING WAS ATTACHED TO THE TOP CRANKCASE BY FOUR 6MM PAN HEAD SCREWS AND WAS SEALED WITH TWO 18MM O`RINGS.THIS ONE-PIECE HOUSING WAS REPLACED WITH A TWO PIECE SET UP WHEN THE OPTIONAL OIL COOLER KIT WAS FITTED, ALLOWING OIL TO FLOW THROUGH THE COOLER AND RETURN TO THE SAME PLACE.THIS OIL COOLER KIT WAS AVAILABLE FROM DEALERS UNDER THE PART NUMBER 99990-524. RETAIL PRICE OF THIS KIT IN 1973 WAS AROUND £35.00.THE OIL CIRCULATED THE ENGINE ON A VERY LOW PRESSURE, BUT THE USE OF ROLLER BEARING THROUGHOUT THE MOTOR MEANT THIS WAS MORE THAN ADEQUATE.

POSITIVE CRANKCASE VENTILATION:

KAWASAKI WAS VERY PROUD OF THIS SYSTEM AND MENTIONED IT IN ALL THEIR SALES BLURB. "PCV" THEY CALLED IT, FOR SHORT.IT WAS BASICALLY JUST A METHOD OF RETURNING UN-BURNT FUEL BACK TO THE AIR FILTER SYSTEM.WHEN UN-BURNT FUEL SLIPPED PAST THE RINGS, INTO THE CRANKCASES, IT WAS ROUTED TO THE BACK OF THE CASES BEFORE IT COULD CONTAMINATE THE OIL.IT THEN EXITED THROUGH A BREATHER SYSTEM, CONSISTING OF A METAL PLATE AND TWO SHAPED RUBBER PIPES, AND THEN THROUGH A 'S' SHAPED RUBBER PIPE UP INTO THE BOTTOM OF THE AIR BOX WHERE IT COULD BE RE-BURNT. THIS GAVE A SIGNIFICANT REDUCTION IN HYDROCARBON EMISSIONS.THE DOWN SIDE WAS THAT ENGINE OIL COULD ALSO ESCAPE AND FIND ITS WAY INTO THE AIR BOX AND CLOG THE AIR FILTER ELEMENT. KAWASAKI LATER ADDRESSED THIS PROBLEM.THE CRANKCASE BREATHER WAS COVERED BY A LARGE POLISHED ALLOY DOMED COVER AND SEALED WITH A LARGE 91MM O`RING. A SPECIAL HOLLOW 10MM BOLT AND SMALL O`RING SECURED IT TO THE CRANKCASES.

ALTERNATOR AND STARTER CLUTCH:

THE CHARGING SYSTEM ON THE Z1 WAS A THREE PHASE SYSTEM, CONSISTING OF A MAGNETIC ROTOR AND COIL WOUND STATOR, MADE BY THE KOKUSAN COMPANY OF JAPAN, WHO ALSO MADE THE VOLTAGE REGULATOR. THE MODEL NUMBER FOR THE GENERATOR WAS AR3703.THE STATOR WIRES WERE WOUND TO A METAL RING AND COATED WITH A CLEAR RESIN. THIS WAS THEN BOLTED TO THE INSIDE OF THE LEFT HAND FRONT ENGINE COVER BY THREE 6MM ALLEN BOLTS.THE WIRING RAN FROM THIS, THROUGH A SQUARE RUBBER GROMMET, AND UP TO MAIN ELECTRICAL PLATE UNDER THE RIGHT HAND SIDE PANEL. IT CONNECTED TO THE CENTRE LOOM BY A BLUE SIX-PIN BLOCK CONNECTOR.ATTACHED TO THE ALTERNATOR WIRING WAS TWO MORE WIRES, ONE FOR THE NEUTRAL SWITCH AND THE OTHER FOR THE OIL PRESSURE SWITCH. THE OIL PRESSURE SWITCH CONNECTION WAS SCREWED TO THE WHITE PLASTIC SWITCH AND PROTECTED BY A BLACK RUBBER CAP.

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KEYED TO THE TAPERED SHAFT ON THE CRANK WAS THE ROTOR. A 8MM BOLT AND A THICK WASHER SECURED THIS.BOLTED TO THE BACK OF THE ROTOR BY THREE 8MM ALLEN BOLTS WAS THE ONE WAY STARTER CLUTCH ASSEMBLE. RUNNING IN THE CENTRE OF THIS CLUTCH WAS THE METAL STARTER GEAR. THIS 71 TOOTHED GEAR ENGAGED WITH THE SMALLER INTERMEDIATE IDLER GEAR WHICH IN TURN ENGAGED WITH THE STARTER MOTOR.THE STARTER GEAR MADE A CONNECTION TO THE CLUTCH BY THREE PINS, THREE SPRINGS, AND THREE ROLLERS. IT RAN, ON THE CRANKSHAFT, ON A SMALL 22MM NEEDLE ROLLER BEARING WITH A THRUST WASHER ON EACH SIDE.THE WHOLE ASSEMBLY RAN IN OIL, WHICH WAS, SUPPLIED THROUGH A HOLE IN THE CRANKCASE HALVES.BETWEEN THE LARGE STARTER GEAR AND THE CRANKCASE WAS A RUBBER COATED METAL SPACER RING THAT CAME IN THREE DIFFERENT THICKNESS', 6.3MM, 7.3MM AND 8.3MM. THE CORRECT SIZE WAS FITTED WHEN ASSEMBLED BY KAWASAKI TO TAKE UP ANY CLEARANCE BETWEEN THE TWO.IT BECAME APPARENT ALMOST IMMEDIATELY THAT EXCESSIVE WEAR WAS APPEARING IN THE SMALL NEEDLE ROLLER BEARING AND IN THE STARTER GEAR.THIS WAS CAUSED BY ECCENTRIC ROTATION OF THE RUBBER DAMPER. THE STARTER GEAR WAS MODIFIED TO INCORPORATE A CIRCULAR RIDGE HELPING TO CENTRALISE THE DAMPER RUBBER. TO EFFECT THIS MODIFICATION, THE ROTOR, SPACER AND RUBBER DAMPER WAS ALSO REPLACED. THE NEW NUMBERS WERE AS FOLLOWS:

OLD NUMBER NEW NUMBERGEAR 21167-001 21167-003ROTOR 21007-023 21007-029SPACER 92026-085 92026-092DAMPER 92075-186 92075-192DAMPER 92075-187 92075-193DAMPER 92075-188 92075-194

THE MODIFIED PARTS WERE FITTED FROM FRAME NUMBER Z1F-6396 ONWARDS.

OUTER ENGINE CASES:

ALTERNATOR CASE.THIS COVER WAS SCREWED TO THE FRONT LEFT HAND CRANKCASE BY 6MM PAN HEAD SCREWS AND SEALED WITH A PAPER GASKET. IT WAS HIGHLY POLISHED AND CARRIED THE LEGEND "DOHC". THE AREA SURROUNDING THE LEGEND WAS FINISHED IN BLACK.

INNER TRANSMISSION COVER.THIS COVER WAS FINISHED IN A NATURAL UN-POLISHED FINISH. IT WAS SECURED BY 6MM PAN HEAD SCREWS AND SEALED WITH A PAPER GASKET.THERE WERE THREE OIL SEALS PRESSED INTO THE COVER, ONE FOR THE CLUTCH PUSH ROD, ONE FOR THE GEAR CHANGE SHAFT AND ONE FOR THE GEARBOX OUTPUT SHAFT. THE PLASTIC NEUTRAL SWITCH ALSO SCREWED INTO THIS COVER.SCREWED TO THIS COVER WAS A THIN METAL PLATE, WHICH OFFERED SOME PROTECTION TO THE CLUTCH RELEASE IN THE EVENT OF THE REAR DRIVE CHAIN BREAKING.

FRONT SPROCKET COVER:THIS WAS A HIGHLY POLISHED COVER BOLTED TO THE LEFT HAND REAR CRANKCASE BY FOUR ZINC PLATED 6MM BOLTS. TWO OF THE BOLTS WERE LOCATED WITH SMALL DOWEL PINS.TWO OIL SEALS WERE FITTED TO THIS COVER WHERE THE GEAR CHANGE SHAFT RAN THROUGH.THE CLUTCH RELEASE MECHANISM WAS ATTACHED TO THIS COVER AS WAS THE REAR DRIVE CHAIN OIL PUMP. A SMALL HOLE IN THE BOTTOM OF IT ALLOWED THE CLUTCH CABLE TO PASS THROUGH ON ITS WAY TO THE RELEASE LEVER.

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IN THE CENTRE OF THE COVER WAS ANOTHER SMALLER PEAR SHAPED COVER, HIGHLY POLISHED AND SECURED BY TWO 6MM PAN HEAD SCREWS. THIS COVER NEEDED TO BE REMOVED IF ACCESS TO THE CLUTCH ADJUSTER OR OIL PUMP WAS REQUIRED. A PAPER GASKET FITTED BEHIND THIS COVER BUT WAS NOT REALLY REQUIRED.

INNER POINTS COVER.THIS WAS A CIRCULAR, HIGHLY POLISHED COVER AND WAS SECURED TO THE FRONT RIGHT HAND CRANKCASE BY 6MM PAN HEAD SCREWS. IT WAS SEALED BY A PAPER GASKET AND IN THE MIDDLE OF IT WAS A SMALL OIL SEAL.THIS COVER HOUSED THE POINTS PLATE ASSEMBLY AND THE AUTOMATIC TIMING ADVANCER.

POINTS COVER.THIS WAS A HIGHLY POLISHED CIRCULAR COVER EMBOSSED WITH THE LEGEND "DOHC". THE AREA SURROUNDING THE LEGEND WAS FINISHED IN BLACK.IT WAS SECURED TO THE INNER POINTS CAP BY TWO 6MM PAN HEAD SCREWS AND SEALED WITH A CIRCULAR PAPER GASKET.

CLUTCH COVER.THIS WAS A LARGE FLAT HIGHLY POLISHED COVER, SEALED BY A PAPER GASKET AND SECURED WITH 6MM PAN HEAD SCREWS TO THE REAR RIGHT HAND CRANKCASE.ON THE BOTTOM OF THE COVER WAS AN OIL SIGHT GLASS WHERE THE OIL LEVEL COULD BE INSPECTED. THIS GLASS WAS SEALED IN A RUBBER RING AND PRESSED INTO THE COVER. TWO PARALLEL LINES, CAST INTO THE COVER, NEXT TO THE SIGHT GLASS HELPED TO DETERMINATE THE OIL LEVEL.

KICK-START COVER.THIS WAS A SMALL BLACK OBLONG COVER, SEALED TO THE REAR OF THE RIGHT HAND CRANKCASE BY A PAPER GASKET AND SECURED BY FOUR 6MM PAN HEAD SCREWS. AN OIL SEAL WAS FITTED TO THE CENTRE OF IT WHERE THE KICK-START SHAFT PROTRUDED THROUGH.ABOVE IT , EMBOSSED INTO THE CRANKCASE ITSELF, WAS THE LEGEND "KICK-STARTER". IN CASE YOU WEREN'T SURE !!.

SUMP COVER.THIS COVER WAS HIGHLY FINNED FOR COOLING, FINISHED IN A NATURAL UN-POLISHED ALLOY AND SEALED TO THE BOTTOM OF THE CRANKCASES BY A LARGE PAPER GASKET AND A 91MM O`RING. IT WAS BOLTED TO THE CRANKCASES BY SEVENTEEN ZINC PLATED 6MM BOLTS AND WASHERS.THERE WAS A LARGE CIRCULAR HOLE IN THE SUMP PLATE WHERE THE OIL FILTER LIVED. HOLDING THE FILTER IN WAS AN ALLOY FINNED CIRCULAR PLATE, WHICH WAS SEALED TO THE SUMP BY A LARGE 105MM O`RING. A SMALL 8MM BOLT AND O`RING SCREWED INTO THE FILTER PLATE TO ASSIST IN OIL REMOVAL.THROUGH THE CENTRE OF THE FILTER COVER RAN A SPECIAL HOLLOW BOLT. THIS BOLT WAS FITTED WITH A 16 MM O`RING AT THE BOTTOM AND PUSHED UP THROUGH A COILED SPRING, A FLAT STEEL WASHER AND THEN THE FILTER ELEMENT ITSELF. THIS THEN SCREWED INTO THE BOTTOM CRANKCASE HOLDING EVERYTHING TOGETHER. THE HEAD OF THIS BOLT WAS 14MM SPANNER SIZE.A LITTLE FURTHER FORWARD ON THE SUMP PLATE WAS ANOTHER THREADED HOLE IN TO WHERE THE MAIN OIL DRAIN PLUG FITTED. THIS WAS A MAGNETIC TYPE PLUG AND WAS SEALED WITH A 22 MM O`RING. THE HEAD OF THE PLUG HAD A 17MM SPANNER SIZE NUT BUILT INTO IT AND IT WAS HOLLOW. IT WAS LATER MODIFIED TO A SOLID DESIGN BUT KEPT THE SAME PART NUMBER.

CARBURETTORS:

THE Z1 WAS FITTED WITH FOURVM28 MM MIKUNI UNITS. THEY WERE ALL MOUNTED TO A SINGLE PLATE SO THAT THEY COULD BE REMOVED AS A SINGLE UNIT.

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THEY WERE CONVENTIONAL TYPE SLIDE CARBS AND WERE SPECIALLY DESIGNED BY MIKUNI FOR KAWASAKI.THE CARB SLIDES WERE ALL CONNECTED BY A SERIES OF ARMS AND ADJUSTERS. A SINGLE CROSS-ROD HELD A PULLEY WHEEL TO WHICH THE TWO THROTTLE CABLES ATTACHED TO, THUS ENSURING ALL THE SLIDES WOULD OPEN AND CLOSE TOGETHER.THERE WAS A SINGLE THROTTLE STOP SCREW TO ADJUST THE TICK OVER AND EACH CARB HAD ITS OWN CHOKE ASSEMBLY. THESE CHOKES WERE ALSO CONNECTED BY A SINGLE ROD AND OPERATED BY A SMALL LEVER ON THE LEFT HAND SIDE. THE LEVER HAD A SMALL RUBBER BLACK BOOT ON IT.EACH CARB BODY WAS FINISHED IN A NATURAL CAST FINISH, WHILE THE TOP COVERS AND FLOAT BOWLS WERE POLISHED ALLOY. THE OUTSIDE TWO MORE POLISHED THAN THE INNER TWO. THE CAPS WERE SECURED BY TWO 4 X 16 MM PAN HEAD SCREWS WHILE THE BOWLS USED FOUR EACH OF THE SAME SCREWS.ON THE BOTTOM OF EACH FLOAT BOWL WAS A LARGE REMOVABLE NUT WHICH GIVE EASY ACCESS TO THE MAIN JETS.SCREWED INTO THE SIDE OF EACH CARB BODY, AT AN ANGLE, WAS A PILOT AIRSCREW.THE FUEL WAS SUPPLIED BY TWO BLACK RUBBER PIPES FROM THE FUEL TAP WHICH CONNECTED TO A "T" PIECE BETWEEN EACH PAIR OF CARBS AND SECURED BY SMALL METAL CLIPS.ANOTHER TWO "T" PIECE CONNECTIONS, A LITTLE HIGHER UP, BETWEEN EACH PAIR OF CARBS HELD ANOTHER BLACK RUBBER PIPE, AGAIN SECURED BY SMALL METAL CLIPS. THESE WERE AIR OUTLET PIPES AND JUST EXITED INTO THE AIR UNDERNEATH THE FUEL TANK.CONNECTED TO THE BOTTOM OF EACH FLOAT BOWL WAS A THIN BLACK RUBBER TUBE WHICH WERE THE FUEL OVERFLOW PIPES. THESE WERE SECURED BY SMALL WIRE CLIPS AND HELD TOGETHER AT THE BOTTOM BY THE RUBBER CLAMP ON THE REAR RIGHT HAND TOP ENGINE MOUNTING SPACER. THIS ENSURED ANY FUEL OVERFLOW WOULD EXIT UNDERNEATH THE BIKE, OUT OF HARMS WAY.ADJUSTMENT WAS BEST LEFT TO THE DEALER DUE TO THE REQUIREMENT OF SPECIAL VACUUM GAUGES.IN STANDARD TRIM, WITH THE CORRECT AIR BOX AND EXHAUST FITTED, THE CARBS WORKED VERY WELL, BUT FITTING NON STANDARD PARTS WOULD SOON RESULT IN POOR PERFORMANCE.

CHAPTER FOUR

THE 1974 Z1-A: STARTING FRAME NO: Z1F-020001-Z1F-047499

IN AUGUST OF 1973, KAWASAKI BEGAN PRODUCTION OF THE 1974 MODEL Z1-A.KAWASAKI WERE MORE THAN HAPPY WITH THE WAY THE Z1 HAD GONE, SO MINIMAL CHANGES WERE PLANNED FOR THIS SECOND YEAR MODEL.THERE HAD BEEN A FEW MINOR PROBLEMS BUT KAWASAKI WERE ON TOP OF THEM AND MOST WERE ADDRESSED IN THE Z1-A.KAWASAKI MOTORS UK HAD BEEN FORMED IN THE FIRST PART OF 1974 AND IN THE CAPABLE HANDS OF JOHN NORMAN, THEY IMPROVED THEIR IMAGE AND CUSTOMER SATISFACTION LEVELS TO AN ALL TIME HIGH. INCREASED SALES OF THE Z1 MODEL FOLLOWED, ENSURING A PERFECT START FOR THE NEW COMPANY.

MAJOR CHANGES:

BODYWORK: CANDY BROWN OR CANDY YELLOW.

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OFFERED FOR 1974 WERE TWO NEW DESIGNS OF DECOR. WHILE THE SAME BASIC COLOURS REMAINED THE SAME, BROWN OR GREEN, THE STRIPING WAS RADICALLY DIFFERENT.THE DESCRIPTION OF THE COLOURS WAS NOW ASSIGNED TO THE ACTUAL COLOUR OF THE STRIPES ON THE TANK AND THE TAILPIECE. THIS WAS AT FIRST A BIT CONFUSING BUT OBVIOUS WHEN OBSERVED.THE MAIN COLOURS WERE ACTUALLY DIFFERENT TO THE 1973 MODEL, BEING A SHADE DARKER. THE BROWN OPTION NOW CAME WITH A THICK ORANGE STRIPE ALONG THE SIDE OF THE TANK WITH A THINNER WHITE STRIPE ABOVE IT. FURTHER UP, ABOVE THE TANK BADGES, RAN TWO MORE THIN ORANGE STRIPES.THE TAILPIECE CONTINUED THE ORANGE STRIPE ALONG ITS SIDE WITH THE THINNER WHITE STRIPE ABOVE IT.THE SIDE PANELS, LIKE THE 1973 MODEL, WERE LEFT JUST IN THE MAIN BODY COLOUR AND THE SIDE PANEL EMBLEMS REMAINED THE SAME AS WELL.THE TANK EMBLEMS HOWEVER WERE MODIFIED AND ENLARGED TO 180MM LONG.THE GREEN OPTION USED THE SAME FORMAT BUT REPLACED THE ORANGE STRIPES WITH BRIGHT YELLOW STRIPES.NO TOUCH UP PAINT WAS OFFERED FOR THIS MODEL.

NEW PART NUMBERS:FUEL TANK 51001-096-2E BROWN/ORANGEFUEL TANK 51001-096-2F GREEN/YELLOWTAIL FAIRING 53043-004-2E BROWN/ORANGETAIL FAIRING 53043-004-2F GREEN/YELLOWSIDE COVER LH 36001-036-2E BROWNSIDE COVER RH 36007-030-2E BROWNSIDE COVER LH 36001-036-2F GREENSIDE COVER RH 36007-030-2F GREENTANK EMBLEM LH 56013-054TANK EMBLEM RH 56014-049

INSTRUMENTS:

THE SPEEDOMETER STAYED THE SAME BUT THE TACHOMETER WAS MODIFIED.THE FACE OF THE TACHOMETER NOW HAD A SMALL RED LIGHT ON IT WITH THE WORDS "STOP LAMP" ABOVE IT. THIS WAS THE BRAKE LIGHT FAILURE WARNING LIGHT. WHEN THE BRAKES WERE APPLIED THE LIGHT WOULD GLOW, BUT IF THE TAILLIGHT BULB HAD BLOWN, THE LIGHT WOULD FLASH ON AND OFF TO WARN YOU SOMETHING WAS AMISS. THE IDIOT LIGHT WARNING CONSOLE WAS ALSO MODIFIED. THE ORDER OF THE LIGHTS WAS CHANGED, NOW THE RUNNING ORDER WAS, FROM LEFT TO RIGHT, TURN, NEUTRAL, HIGH BEAM, AND OIL. THE WORDING FOR THESE LIGHTS WAS NOW PRINTED BELOW THE LIGHTS AND NOT ABOVE LIKE THE 1973 Z1 MODEL.BECAUSE OF THIS THE INSTRUMENT WIRING LOOM WAS ALSO CHANGED TO INCLUDE THE EXTRA WIRES REQUIRED FOR THE STOP LAMP WARNING BULB. THE MOUNTING BRACKET FOR THE METERS WAS ALSO MODIFIED IN ORDER TO ACCEPT THIS NEW TACHOMETER.

NEW PART NUMBERS:TACHOMETER 25015-025METER LOOM 25011-042IDIOT LIGHT COVER 25023-011METER BRACKET 25008-036

SWITCHGEAR:

THE LEFT HAND SWITCH REMAINED THE SAME BUT THE RIGHT HAND SWITCH WAS MODIFIED. IT NO LONGER HAD THE FRICTION ADJUSTING SCREW FITTED.

NEW PART NUMBER:SWITCH RH 46132.005

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HORN:THE Z1-A WAS NOW FITTED WITH THE MODIFIED HORN ASSEMBLY THAT WAS FIRST FITTED TO THE LATE 1973 MODELS.NEW PART NUMBER:HORN 27003-053

MAIN WIRING LOOM:THE LOOM ON THE Z1-A WAS MODIFIED TO ACCEPT THE NEW BRAKE LIGHT FAILURE FEATURE. A SMALL THREE PIN FEMALE PLUG CONNECTION WAS ADDED NEAR THE IGNITION COIL CONNECTIONS.THE STOP LAMP FAILURE SWITCH WAS A SMALL RUBBER COATED SQUARE ITEM ATTACHED TO A ZINC PLATED METAL BRACKET AND BOLTED TO ONE OF THE IGNITION COIL MOUNTINGS. RUNNING FROM THE SWITCH WAS A WHITE MALE THREE PIN PLASTIC PLUG CONNECTOR.NEW PART NUMBER:MAIN LOOM 26001-111FAILURE SWITCH 28019-001SWITCH BRACKET 32060-014

HEADLAMP:DUE TO PROBLEMS STILL PERSISTING WITH HEADLAMP BULB FAILURE, UK MODEL WERE FITTED WITH A 20W RESISTOR. THIS WAS WIRED INTO THE LIGHTING SYSTEM, CONNECTING BETWEEN THE TWO BLUE WIRES RUNNING FROM THE HANDLE BAR SWITCHES. THE RESISTOR WAS A GREEN CIGAR SHAPED UNIT, BOLTED TO A BLACK METAL BRACKET AND SANDWICHED BETWEEN ONE OF THE IGNITION COIL MOUNTS AND THE FRAME.NEW PART NUMBERS:RESISTOR 26019-005BRACKET 32122-034BOLT 110B0863 + 461F0800 WASHER + 310B0800 NUT.

VOLTAGE REGULATOR:THE MODIFIED REGULATOR, FIRST USED ON THE 1973 Z1, WAS NOW FITTED AS STANDARD ON FRAME NUMBERS Z1F-36187 ONWARDS.NEW PART NUMBER:VOLTAGE REGULATOR 21066-019.

VOLTAGE RECTIFIER:THE RECTIFIER WAS MODIFIED AND WAS NOW FINISHED IN SILVER, NOT BLACK.NEW PART NUMBER:VOLTAGE RECTIFIER 21061-019

HEADLAMP BRACKETS:THE DESIGN OF THESE CHROME BRACKETS WAS CHANGED ON THE Z1-ATHEY WERE NO LONGER SEAMLESS, THE TRIANGULAR PART BEING QUITE PROUD OF THE CYLINDRICAL SECTION.NEW PART NUMBERS:BRACKET LH 44033-071BRACKET RH 44034-071

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INDICATORS:THE INDICATOR HEADS WERE NOW FITTED WITH DIFFERENT LENSES FRONT AND REAR. THE REAR ONES WERE NOW FROSTED TO STOP ANY CHANCE OF DAZZLING FOLLOWING TRAFFIC. BECAUSE OF THIS THE WHOLE ASSEMBLY WAS MODIFIED.NEW PART NUMBERS:FRONT LAMP 23040-047REAR LAMP 23040-048FRONT LENS 23048-012REAR LENS 23048-013

DRIVE CHAIN ADJUSTERS:THE ADJUSTER PLATES WERE MODIFIED TO ACCEPT 10MM BOLTS INSTEAD OF 8MM BOLTS. THIS WAS DUE TO COMPLAINTS OF BENT AND BROKEN ADJUSTERS ON THE 1973 MODEL. THE LOCK NUTS WERE ALSO CHANGED TO 10MM.BECAUSE OF THE EXTRA THICKNESS OF THESE PLATES THE REAR AXLE SPACER BETWEEN THE SPROCKET CARRIER AND SWING ARM WAS ALSO MODIFIED.NEW PART NUMBERS:PLATES 33040-063BOLTS 92001-143NUTS 314B1000SPACER LH 42037-023

REAR BRAKE PANEL:THE BRAKE PANEL WAS NOW EQUIPPED WITH A BRAKE WEAR INDICATOR. THIS CONSISTED OF A SMALL SEMI-CIRCULAR DECAL STUCK TO A RECESS ON THE BRAKE PLATE NEXT TO THE BRAKE CAMSHAFT. A SMALL CHROME TRIANGULAR POINTER WAS FITTED OVER THE SPLINES OF THE CAMSHAFT WHICH WAS ALSO MODIFIED TO ACCEPT THE POINTER. THE CHROME BRAKE ARM WAS ALSO MODIFIED SO THAT THE 8MM CLAMPING BOLT COULD BE FITTED FROM THE OPPOSITE SIDE SO THAT IT WOULD NOT OBSTRUCT THE POINTER.NEW PART NUMBERS:BRAKE PLATE 42006-053CAMSHAFT 41050-017POINTER 41085-004BRAKE ARM 42029-033

MUFFLERS:THE MUFFLERS ON THE UK MODELS WERE MODIFIED AND NOW FITTED WITH THE REMOVABLE BAFFLES. A SMALL BAR ACROSS THE END OF THE BAFFLE ASSISTED IN REMOVAL.NEW PART NUMBERS:MUFFLER LH UPPER 18001-127MUFFLER LH LOWER 18001-128MUFFLER RH LOWER 18001-129MUFFLER RH UPPER 18001-130BAFFLE 18033-068

FRONT BRAKE MASTER CYLINDER:A MODIFIED MASTER CYLINDER WAS FITTED TO THE Z1-A. THIS INCORPORATED A MODIFIED FRONT BRAKE LEVER AND ADJUSTING BOLT.NEW PART NUMBER:MASTER CYLINDER 43015-009 UK MODELMASTER CYLINDER 43015-012 US MODEL

FRONT BRAKE METAL PIPE:THE METAL BRAKE PIPE ON THE Z1-A WAS CHANGED TO A SLIGHTLY DIFFERENT SHAPE AND WAS A DARKER FINISH

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NEW PART NUMBER:BRAKE PIPE 43060-009

TOP YOKE REAR MOUNTING BOLT:A CHROME 8MM-DOMED NUT INSTEAD OF JUST A NORMAL NUT BOLT NOW SECURED THE TOP YOKE MOUNTING.NEW PART NUMBER:NUT 92090-007

MAIN STAND MOUNTING BOLTS:THESE TWO BOLTS WERE NOW OF A SOLID DESIGN, NOT HOLLOW.THE PART NUMBER REMAINED THE SAME, 34019-014.

ENGINE CHANGES:

PERHAPS THE MOST OBVIOUS AND IMPORTANT CHANGE ON THE Z1-A WAS THE USE OF A NATURAL ALLOY SILVER FINISH ON THE ENGINE.OWNER'S IN COUNTRIES WHERE THE WEATHER CONDITIONS WAS LESS THAN PERFECT COMPLAINED OF THE BLACK PAINT PEELING FROM THE ENGINE PARTS.KAWASAKI LISTENED TO THESE COMPLAINTS AND LEFT THE CRANKCASES, CYLINDER BARRELS, CYLINDER HEAD, CAMSHAFT COVER AND KICK-START COVER IN THEIR NATURAL SILVER FINISH.THIS WAS CONSIDERED A GOOD MOVE BY CUSTOMERS AND DEALERS ALIKE, AND SO THE SILVER FINISH CONTINUED ON ALL SUBSEQUENT Z1 MODELS.THE TWO PIECE HEAD GASKET, FIRST USED ON LATER Z1 MODELS, WAS NOW STANDARD ON THE Z1-A, AS WAS THE TALLER CYLINDER HEAD NUTS ALONG WITH ANY OTHER MODIFICATIONS ORIGINALLY MADE TO THE Z1 ENGINE.

LEFT HAND REAR SPROCKET COVER:THIS ENGINE CASE WAS CHANGED SLIGHTLY TO ACCEPT THE NEW MODIFIED CHAIN OILER PUMP.EMBOSSED ONTO THE FACE OF THE ENGINE SPROCKET COVER, FOR THE FIRST TIME, WAS THE GEARBOX GEAR CHANGE PATTERN. NEW PART NUMBER:COVER LH REAR 14026-026

DURING 1974 VARIOUS OTHER MODIFICATIONS WERE MADE TO THE Z1-A, SOME MADE PUBLIC AND SOME KEPT SECRET.

THE FRONT CAM CHAIN SLIPPER TENSIONER BLADE HAD A HABIT OF BREAKING IN HALF AND FALLING INTO THE SUMP. THIS CAUSED EXCESSIVE VIBRATION FROM THE CAM CHAIN AND POSSIBLE DAMAGE TO THE CYLINDER BARREL. A STRONGER TENSIONER BLADE WAS PRODUCED UNDER THE NEW PART NUMBER 12053-019. MAJOR ENGINE SURGERY, HOWEVER, WAS REQUIRED.

THE CAM CHAIN ADJUSTER HOUSING AT THE BACK OF THE BLOCK WAS FOUND TO HAVE CRACKS APPEARING IN THEM, SO A REPLACEMENT BODY WAS PRODUCED UNDER THE NEW PART NUMBER 12047-003. THIS WAS A LARGER THICKER UNIT.

THE FOUR PAN HEAD SCREWS HOLDING THE OIL PRESSURE SWITCH HOUSING ONTO THE CRANKCASES COULD EASILY BE CHEWED UP, SO THEY WERE REPLACED WITH CROSS HEADED BOLTS INSTEAD. THE PART NUMBER FOR THESE WAS 92003-145.

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IN JANUARY 1974, KAWASAKI RELEASED A SERVICE BULLETIN CONCERNING PERSISTENT OIL LEAKS FROM THE CYLINDER BARREL JOINT. DEALERS WERE INSTRUCTED TO REMOVE THE FOUR MIDDLE CRANKCASE STUDS AND RE-SEAL THEM INTO THE CASES BY USING A LIQUID GASKET. THIS WAS TO STOP THE ENGINE OIL FROM SEEPING UP THE THREADS ON THE STUDS.

ALSO IN JANUARY 1974, THE AUTOMATIC TIMING ADVANCER WAS MODIFIED ALONG WITH THE CARBURETTORS. THIS WAS IN AN EFFORT TO INCREASE PERFORMANCE.TIMING WAS NOW TO BE SET AT 20 DEGREES BTDC @ 1500 RPM INSTEAD OF 5 DEGREES BTDC. A NEW ADVANCER UNDER THE PART NUMBER 21148-005 WAS MADE AVAILABLE AS A DIRECT SUPERSESSION.THE CARBS HAD CHANGES MADE TO VARIOUS INTERNAL PARTS INCLUDING THE FLOATS, PILOT JETS, NEEDLE JETS, THROTTLE VALVES AND CHOKE PLUNGERS. THE SHAPE OF THE FLOAT BOWL AND GASKET WAS ALSO CHANGED. THE CHOKE OPERATING LEVER WAS ALSO MODIFIED.THE MOST OBVIOUS VISUAL DIFFERENCE WAS THE FITTING OF A BRASS DRAIN PLUG, SCREWED INTO THE BOTTOM OF EACH FLOAT BOWL AT AN ANGLE AND SEALED WITH A SMALL O`RING.THE WHOLE CARB ASSEMBLY WAS NOW AVAILABLE UNDER THE NEW PART NUMBER 16001-217 AS A DIRECT SUPERSESSION.THE MODIFIED PARTS WERE FITTED BY THE FACTORY ON ALL BIKES WITH FRAME NUMBERS Z1F-032818 ONWARDS.

IN MARCH 1974, KAWASAKI RELEASED A SERVICE BULLETIN CONCERNING THE REPLACEMENT OF THE DRIVE CHAIN OIL PUMP. DUE TO DIFFICULTIES IN ADJUSTING THE PUMP BY SOME OWNERS, KAWASAKI MODIFIED IT GIVING IT THE NEW PART NUMBER 16082-056. THIS PUMP WAS MUCH EASIER TO ADJUST.KAWASAKI FITTED THE NEW PUMP TO ALL BIKES ON THE PRODUCTION LINE FROM FRAME NUMBER Z1F-039150 ONWARDS.

ALSO IN MARCH 1974, THE RED PLASTIC COVER OVER THE BATTERY LIVE LEAD WAS MADE AVAILABLE AS A SEPARATE SPARE PART. PREVIOUSLY IT WAS ONLY AVAILABLE WITH THE LEAD. THE PART NUMBER FOR THIS COVER WAS 92073-030.

IN APRIL 1974, NEW LEGISLATION REQUIRED THE FITTING TO THE HEADSTOCK OF ALL NEW MOTORCYCLES IN THE UK, A STICKER CONFIRMING THAT THE MOTORCYCLE COMPLIED TO CURRENT RADIO NOISE REQUIREMENTS.THIS WAS A SMALL BLACK STICKER AND THE LEGEND E11 10R-241 WAS PRINTED ON IT IN SILVER.

IN JUNE 1974, SOME MODELS WERE DELIVERED TO THE UK WITH THE WRONG HEADLAMP FITTED. KAWASAKI GIVE PERMISSION TO DEALERS TO REPLACE THEM UNDER WARRANTY. SOME DEALERS, OF COURSE, DID NOT BOTHER CAUSING PROBLEMS LATER ON WHEN REPLACEMENT PARTS WERE REQUIRED.THE PART NUMBER FOR THE SUPPLIED REPLACEMENT HEADLAMPS WAS 23004-035, ALTHOUGH THIS WAS NOT THE SAME PART AS THE ONE FITTED ON THE PRODUCTION LINE FOR THE UK MARKET. THIS CAUSED EVEN GREATER CONFUSION.THE CORRECT HEADLAMP SHOULD HAVE BEEN PART NUMBER 23004-058.

OWNER`S HANDBOOK: PART NUMBER 99997-808

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CHAPTER FIVE

THE 1975 Z1-B STARTING FRAME NO: Z1F-047500 - Z1F-085700

IN JUNE OF 1974, KAWASAKI BEGAN PRODUCTION OF THE 1975 MODEL Z1-B.SALES OF THE Z1 MODEL WERE STILL INCREASING SO KAWASAKI WERE RELUCTANT TO MAKE ANY RADICAL CHANGES.THE BIKE REMAINED BASICALLY THE SAME FOR 1975, HOWEVER MORE PROBLEMS THAT HAD COME TO LIGHT WERE ADDRESSED AND MODIFICATIONS WERE MADE.

BODYWORK: CANDY SUPER BLUE OR CANDY SUPER RED.

AFTER THE CONFUSION WITH THE DESCRIPTION OF THE 1974 MODELS, KAWASAKI RESORTED TO DESCRIBING THESE NEW COLOURS BY THEIR BASE COLOURS.BOTH COLOUR OPTIONS WERE GIVEN THE SAME COLOUR OF STRIPES. THIS WAS A THICK GOLD STRIPE RUNNING ALONG THE BOTTOM OF THE FUEL TANK WITH A THINNER WHITE STRIPE ABOVE IT.ABOVE THE TANK EMBLEMS WAS A THICK BLACK STRIPE EDGED WITH A THIN WHITE STRIPE ON EACH SIDE OF IT.THE TAIL FAIRING HAD THE GOLD STRIPE AND THE THIN WHITE STRIPE REPEATED ON IT. UNLIKE THE 1974 Z1-A MODEL, THIS STRIPE CURVED UPWARDS TOWARDS THE CENTRE OF THE TAILPIECE. THE TRAY INSIDE THE TAILPIECE NOW CONTAINED A DIFFERENT DECAL. INSTEAD OF THE SILVER DECAL WITH THE WIRING DIAGRAM ON IT, THERE WAS NOW A WHITE DECAL SHOWING AN OUTLINE OF THE BIKE AND REMINDING THE OWNER OF THE DAILY SAFETY CHECKS THAT SHOULD BE CARRIED OUT.THE SIDE PANELS, ONCE AGAIN, WERE PAINTED JUST IN THE MAIN BODY COLOUR.THE SIDE PANEL EMBLEMS WERE CHANGED FOR THIS MODEL. THE '900' LEGEND ON THE BADGE WAS NOW MUCH LARGER THAN PREVIOUS MODELS. THE REST OF THE EMBLEM REMAINED THE SAME.THE FUEL TAP WAS ALSO CHANGED TO A NATURAL SILVER FINISH INSTEAD OF THE BLACK DESIGN PREVIOUSLY USED.NO TOUCH UP PAINT WAS OFFERED FOR ANY OF THESE NEW COLOURS.

NEW PART NUMBERS:FUEL TANK 51001-096-2R REDFUEL TANK 51001-096-2S BLUETAIL FAIRING 53043-004-2R REDTAIL FAIRING 53043-004-2S BLUESIDE COVER LH 36001-036-2R REDSIDE COVER RH 36007-030-2R REDSIDE COVER LH 36001-036-2S BLUESIDE COVER RH 36007-030-2S BLUEPANEL EMBLEM 56018-197 LHPANEL EMBLEM 56018-198 RHEMBLEM CLIPS 92018-005

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FUEL TAP 51023-043

INSTRUMENTS:ONLY THE SPEEDOMETER WAS CHANGED ON THE Z1-B. THE NUMERALS ON THE CLOCK FACE WERE NOW IN INCREMENTS OF 10MPH INSTEAD OF 20MPH.

NEW PART NUMBER:SPEEDOMETER 25005-121

SWITCHGEAR:BOTH SWITCHGEAR ON THE Z1-B WAS CHANGED. THE RIGHT HAND SWITCH WAS COSMETICALLY CHANGED WHILE THE LEFT HAND SWITCH ASSEMBLY WAS FITTED WITH A COMBINED HORN AND HEADLAMP FLASHER ROCKER SWITCH. ON THE AMERICAN MODEL, THE FLASHER PART OF THE SWITCH WAS INOPERATIVE. THE CITY LIGHT POSITION WAS ALSO REMOVED FROM THE AMERICAN RIGHT HAND SWITCH ASSEMBLY.NEW PART NUMBERS:LH SWITCHGEAR 46091-034RH SWITCHGEAR 46132-024

HEADLAMP:THE UK MODEL WAS NOW FITTED WITH A NON-ADJUSTABLE HEADLAMP UNIT. THIS NEW UNIT, MANUFACTURED BY THE STANLEY COMPANY, DID WITHOUT THE INNER RIM AND ADJUSTING SCREW FROM THE PREVIOUS MODELS.THE AMERICAN MODELS CONTINUED WITH THE SEALED BEAM UNIT AS BEFORE.ANOTHER ATTEMPT TO REDUCE VIBRATION WAS CARRIED OUT BY REPLACING THE HEADLAMP MOUNTING RUBBERS WITH SOFTER ITEMS. BECAUSE OF THIS, THE INDICATOR EARTHING COLLARS WERE ALSO MODIFIED.NEW PART NUMBERS:HEADLAMP ASSEMBLY 23004-066 (UK MODEL)MOUNTING RUBBER 23066-015 INNERMOUNTING RUBBER 23066-016 OUTEREARTH COLLAR 23076-005

FRONT BRAKE MASTER CYLINDER:THE MASTER CYLINDER USED ON THE Z1-B WAS MODIFIED FOR THE UK MARKET. IT NOW INCORPORATED A WHITE PLASTIC RESERVOIR TO ENABLE EASY CHECKING OF THE BRAKE FLUID LEVEL.NEW PART NUMBER:CYLINDER 43015-035

REAR DRIVE CHAIN AND SPROCKETS:DUE TO COMPLAINTS OF THE DIFFICULTIES IN USING THE AUTOMATIC CHAIN OILERS OF PREVIOUS MODELS, THE Z1-B WAS FITTED WITH AN O`RING CHAIN. ANOTHER FIRST FOR KAWASAKI. THE NON O`RING CHAIN WAS NOT REALLY UP THE JOB ANYWAY, SO THIS WAS A GOOD MOVE.THE WHOLE OF THE CHAIN OILER SYSTEM WAS REMOVED.THE CHAIN WAS ONCE AGAIN AN 'ENUMA' PRODUCT, AN EK630S-TO X 92 LINKS.BECAUSE OF THE EXTRA THICKNESS OF THE CHAIN, CAUSED BY THE O`RINGS, MANY OTHER PARTS OF THE BIKE HAD TO BE MODIFIED. THE CHAIN WAS 0.11 OF AN INCH WIDER.THE FRONT DRIVE SPROCKET HAD TO BE SPACED OUT FROM THE INNER TRANSMISSION COVER, SO A MODIFIED SPROCKET WITH A BOSS BUILT INTO THE BACK OF IT WAS PRODUCED. BECAUSE OF THIS, A THINNER LOCKING NUT WAS ALSO SUPPLIED.

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THE REAR SPROCKET REMAINED THE SAME BUT A THIN SPACER WAS FITTED BETWEEN THE SPROCKET AND THE CARRIER TO SPACE IT OUT. BECAUSE OF THIS THE SIX SPROCKET RETAINING BOLTS NEEDED TO BE MADE LONGER.THE PLASTIC CHAIN GUARD WAS ALSO MODIFIED TO A SLIGHTLY WIDER DESIGN AND THE CHAIN ADJUSTER PLATES WERE CHANGED ONCE AGAIN. BOTH REAR ENGINE MOUNTING PLATES WERE MODIFIED, ALTHOUGH THEORETICALLY, ONLY THE LEFT HAND ONE NEEDED TO BE. ONE OF THE 8 X 40 MM BOLTS, HOLDING THE BRACKET TO THE FRAME, WAS SHORTENED TO 36MM.ALSO SHORTENED WAS THE TWO EXHAUST MOUNTING BOLTS. THESE WERE NOW 104 MM LONG INSTEAD OF 108 MM. THE TWO 10MM LOCKING NUTS, AT THE REAR, WERE ALSO MADE THINNER. THIS ENSURED NOTHING TOUCHED THE DRIVE CHAIN.KAWASAKI RECOMMENDED THAT THE NEW O`RING CHAIN SHOULD BE LUBRICATED EVERY 500 MILES.NEW PART NUMBERS:CHAIN 92057-096FRONT SPROCKET 13144-062REAR SPROCKET SPACER 92026-108MOUNTING BOLTS 92003-087 (SPROCKET)ENGINE PLATE 32030-046 LHENGINE PLATE 32030-047 RHMOUNTING BOLT 110G0836 (ENGINE)CHAIN GUARD 36014-061CHAIN ADJUSTER 33040-066ADJUSTER BOLT 92003-147EXHAUST BOLTS 92003-180LOCK NUTS 92019-021

FOOTREST:

THE Z1-B WAS FITTED FOR THE FIRST TIME IN THE UK WITH THE FOLDING FOOTREST THAT THE AMERICAN MODEL HAD ALWAYS HAD.THE FOOTREST RUBBERS WERE NOW BONDED ONTO A ZINC PLATED METAL STEM AND PINNED TO THE GLOSS BLACK METAL FOOTREST BRACKETS. THE FITTINGS TO THE FRAME WAS UNCHANGED.LIKE THE REAR FOOTREST, THE FOLDING FRONT ITEMS USED A CLEVIS PIN, A LARGE FLAT ZINC PLATED WASHER AND A SMALL COTTER PIN TO SECURE IT TO THE BRACKET.AMERICAN MODELS USED A SLIGHTLY DIFFERENT DESIGN OF MOUNTING BRACKETS. THEY WERE THINNER IN PLACES WITH A DIFFERENT BEND TO THEM AND THE CLEVIS PIN SAT FLUSH INTO THEM. THESE DIFFERENT BRACKETS CAUSED THE FOOTREST THEMSELVES TO BE SLIGHTLY MORE FORWARD. I AM NOT TO SURE WHY THIS WAS, PERHAPS TO GIVE THE AMERICAN RIDER A MORE UPRIGHT POSITION.NEW PART NUMBERS:FOOTREST BRACKET 34003-036 LHFOOTREST BRACKET 34003-037 RHFOOTREST BAR 34028-011 LHFOOTREST BAR 34028-012 RHCLEVIS PIN 92043-080WASHER 92022-204COTTER PIN 550D2515

HANDLEBARS:FOR THE FIRST TIME KAWASAKI OFFERED FOR THE UK MODEL, A LOWER SET OF HANDLEBARS. THESE WERE DESCRIBED AS SEMI-LOW. THEY WERE FINISHED IN CHROME AND HAD A RISE OF ABOUT THREE INCHES.

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VARIOUS OTHER PARTS NEEDED TO BE REPLACED IF THESE BARS WERE FITTED INCLUDING SHORTER CABLES AND THE TOP BRAKE HOSE.NOT MANY PEOPLE WENT FOR THIS OPTION, PREFERRING THE SIT UP AND BEG ORIGINAL BARS.NEW PART NUMBERS:HANDLEBARS 46006-013 SEMI-LOWCLUTCH CABLE 54011-070THROTTLE CABLE 54012-112 OPENTHROTTLE CABLE 54012-113 CLOSEBRAKE HOSE 43059-017

FRONT BRAKE CALLIPER:THE TWO ALLEN BOLTS ON WHICH THE INNER BRACKET SLID ON WERE CHANGED.THESE WERE NOW A SMOOTH PLAIN FINISH UNLIKE THE PREVIOUS KNURLED DESIGN. THE PART NUMBER, HOWEVER, WAS UNCHANGED.

FRONT FORKS:THE INNER PISTON DAMPER ASSEMBLY IN EACH FORK LEG WAS CHANGED ON THE Z1-B. PREVIOUSLY THE SMALL METAL BUSH ON THE BOTTOM OF THE DAMPER WAS NOT AVAILABLE SEPARATELY BUT NOW IT WAS. THIS NEW BUSH SAT INSIDE THE BOTTOM OF EACH OF THE FORK INNER TUBES AND WERE SECURED WITH A CIRCLIP. BECAUSE OF THIS A NEW FORK ASSEMBLY WAS MADE AVAILABLE TO CONTAIN ALL THE NEW PARTS. THE AMERICAN MODEL ALSO RECEIVED THE NEW FORKS BUT OF COURSE, THEY CAME SUPPLIED WITH ORANGE REFLECTORS ON THE FORK LOWERS INSTEAD OF THE CHROME CAPS.NEW PARTS:DAMPER ASSEMBLY 44022-021BUSH 44048-009CIRCLIP 44044-019FORK ASSEMBLY 44001-137 (UK)

REAR BRAKE LIGHT SWITCH:THE DESIGN OF THE PLASTIC REAR BRAKE LIGHT SWITCH WAS CHANGED ON THE Z1-B. THE TWO ADJUSTING NUTS WERE NOW THICKER AND THE SWITCH BODY WAS THICKER AND MORE ROBUST.NEW PART NUMBER: 27010-017

ENGINE CHANGES:

ONLY A FEW CHANGES WERE MADE TO THE ENGINE OF THE Z1-B, SUCH WAS ITS RELIABILITY.

CRANKCASES:SLIGHT COSMETIC CHANGES WERE MADE TO THE CRANKCASES ON THE Z1-B.THE PART NUMBER, HOWEVER, WAS NOT CHANGED.

CAMSHAFTS:THE BOLTS HOLDING THE CAMSHAFT SPROCKETS TO THE CAMS WERE MODIFIED AND INSTEAD OF JUST PLAIN BOLTS, HIGH TENSILE FLANGED FASTENERS WERE USED INSTEAD. THESE BOLTS WERE NOW FITTED WITH A LOCKING AGENT DUE TO PROBLEMS WITH PREVIOUS BOLTS COMING LOOSE.NEW PART NUMBER:BOLT 92003-141

CYLINDER HEAD NUTS:

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THE DESIGN OF THE TWELVE CYLINDER HEAD NUTS WAS CHANGED TO MORE OF A BELL SHAPED DOMED STYLE.NEW PART NUMBER:HEAD NUT 92015-076

LUBRICATION SYSTEM:

THERE HAD BEEN REPORTS ON EARLIER MODELS THAT THE OIL PRESSURE WARNING LIGHT HAD BEEN STAYING ON UNDER SEVERE ACCELERATION. THIS WAS PUT DOWN TO A SLIGHT DECREASE IN OIL PRESSURE ON SOME ENGINES. IT WAS ADVISED THAT THE OIL PRESSURE SWITCH SHOULD BE REMOVED AND THE SMALL HOLE IN THE SWITCH SHOULD BE RE-DRILLED TO ALLOW AIR TO ESCAPE MORE QUICKLY. IT WOULD SEEM THAT AERATION OF THE OIL HAD BEEN OCCURRING BY THE SUDDEN MOVEMENT UNDER ACCELERATION. HOWEVER, ON FURTHER INVESTIGATION, THE PROBLEM LAY IN THE OIL PUMP ITSELF. AIR WAS GETTING TRAPPED IN THE PUMP BODY AND KAWASAKI ADVISED DEALERS TO DRILL A SMALL DRAIN HOLE INTO THE PUMP TO ALLOW IT TO ESCAPE. THIS MODIFICATION WAS TO BE CARRIED OUT 'DISCREETLY' BY DEALERS BUT MANY WERE NOT TO IMPRESSED WITH THIS TIME CONSUMING SOLUTION. SPOILT BY THE LACK OF 'SPANNER' WORK THAT THE Z1 NORMALLY REQUIRED, DEALERS PRESSURISED THE FACTORY TO SORT THE PROBLEM OUT AT THEIR END.KAWASAKI WERE NOT GOING TO LET THIS PROBLEM SPOIL THE 'BULLET PROOF' REPUTATION THAT THE Z1 MOTOR HAD EARNED ITSELF, SO THEY CHANGED THE OIL PUMP ON THE ENGINE ASSEMBLY LINE.THE MODIFICATIONS INCLUDED A THICKER GASKET BETWEEN THE TWO PUMP HALVES AND A DIFFERENT OIL STRAINER. THE NEW STRAINER WAS NOW A PUSH IN FIT INSTEAD OF THE PREVIOUSLY SCREWED ON TYPE.THE CHANGES ALSO REQUIRED A SLIGHTLY BIGGER SUMP PLATE TO BE FITTED.NEW PART NUMBERS:OIL PUMP 16082-059SUMP PLATE 16110-003STRAINER 16111-004OIL PUMP GASKET 16145-002

CARBURETTORS:THE Z1-B WAS NOW FITTED WITH THE MODIFIED CARBS FIRST USED ON LATER MODEL Z1-A`S. PART NUMBER 16001-217.

DURING 1975, OTHER MODIFICATIONS WERE MADE AND CARRIED OUT ON THE PRODUCTION LINE AT KAWASAKI.

BEFORE DEALERS RECEIVED SUPPLIES OF THE Z1-B, A BULLETIN WAS SENT OUT TO WARN DEALERS THAT THE FRONT BRAKE LIGHT SWITCH, PART NUMBER 43065-001, ON BIKES BETWEEN FRAME NUMBERS Z1F-57790 AND Z1F-59280 WERE NOT TIGHTENED CORRECTLY. DEALERS WERE ADVISED TO CHECK ALL RELEVANT BIKES AND RE-TIGHTEN THE SWITCH TO 2.8KG-M OF TORQUE.

IN JANUARY OF 1975, DEALERS WERE ADVISED OF THE CHANGES TO THE CRANKCASES AND WARNED TO CHECK OIL LEVELS USING THE MARKS ON THE CLUTCH COVER, BECAUSE THE NEW CASES HELD SLIGHTLY LESS OIL.

IN ADDITION, IN JANUARY OF 1975, A BULLETIN WAS SENT OUT TO DEALERS ADVISING THAT A REPAIR KIT WAS AVAILABLE FOR THE LEFT HAND SWITCHGEAR. THE SMALL SWITCH FOR SELECTING HIGH OR LOW BEAM COULD EASILY BREAK OFF. NORMALLY YOU WOULD HAVE HAD TO BUY THE COMPLETE SWITCHGEAR TO REMEDY THIS BUT NOW A REPAIR KIT WAS OFFERED. THIS KIT FITTED MANY MODELS BECAUSE THIS TYPE OF SWITCH WAS ALSO USED

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ON THE TRIPLE RANGE AND THE Z400 AND Z750 TWINS. THE PART NUMBER FOR THIS KIT WAS 99930-530.

STILL IN JANUARY 1975 AND A SERVICE BULLETIN ADVISED THAT ANOTHER MODIFICATION HAD BEEN MADE TO THE AUTOMATIC TIMING ADVANCER.PUNCH MARKS HAD BEEN ADDED TO THE FACE OF THE UNIT TO ASSIST IN SETTING THE TIMING WHEN FULLY ADVANCED. THE PART NUMBER FOR THIS NEW PART REMAIN UN-CHANGED. THE MODIFIED ADVANCER WAS FITTED TO ENGINE NUMBERS Z1E-058727 ONWARDS.

THE LAST SERVICE BULLETIN OF JANUARY 1975 WAS TO ADVISE OF THE MODIFICATION AND STRENGTHENING OF THE MAIN FRAME AROUND THE HEADSTOCK AREA. A REMINDER OF THE AVAILABILITY OF THE STRENGTHENING KIT, PART NUMBER 99990-532, WAS ALSO MADE. THE MODIFICATIONS WERE MADE TO BIKES AT KAWASAKI FROM FRAME NUMBERS Z1F-065210 ONWARDS.

IN FEBRUARY OF 1975, A BULLETIN WAS SENT TO DEALERS TO ADVISE THAT YET ANOTHER ATTEMPT HAD BEEN MADE TO REDUCE VIBRATION TO THE HEADLAMP AREA. NEW MODIFIED HEADLAMP BRACKETS HAD BEEN PRODUCED AND FITTED TO ALL BIKES FROM FRAME NUMBERS Z1F-55500 ONWARDS.DEALERS WERE ALSO ADVISED TO REMOVE THE HEADLAMP ADJUSTING BRACKET, FASTENED TO THE BOTTOM OF THE HEADLAMP BOWL. KAWASAKI HAD ALREADY BEGUN TO LEAVE THIS BRACKET OFF PRODUCTION BIKES, AT THE SAME TIME THAT THE NEW HEADLAMP BRACKETS WERE FITTED. THE NEW CHROME HEADLAMP BRACKETS NOW HAD AN EXTRA INNER PLATE ON THE INSIDE SECTION OF THE TRIANGULAR PIECE. THIS PLATE SANDWICHED THE PREVIOUSLY MODIFIED MOUNTING RUBBERS AND ALLOWED THE HEADLAMP ASSEMBLY SLIGHTLY MORE MOVEMENT THUS REDUCING VIBRATION.BECAUSE OF THESE CHANGES A NEW FORK ASSEMBLY WAS MADE AVAILABLE TO INCLUDE ALL THE NEW PARTS. AS USUAL THE AMERICAN MODEL WAS THE SAME WITH THE EXCEPTION OF THE ORANGE REFLECTORS.NEW PART NUMBERS:BRACKET 44033-072 LHBRACKET 44034-072 RHFORK ASSEMBLY 44001-163 (UK)

IN SEPTEMBER OF 1975, A BULLETIN WAS SENT TO DEALERS TO ADVISE THEM THAT OWNERS HAD COMPLAINED OF EXHAUST GASES BLOWING AROUND THE SMALL REAR RUBBER PIPE CONNECTORS. TO COMBAT THIS, NEW RUBBER PIPES HAD BEEN PRODUCED ALONG WITH THE MODIFICATION OF THE TWO BOTTOM MUFFLERS. THIS ENSURED A BETTER SEAL BETWEEN THE TWO PAIRS OF SILENCERS.THE NEW PART NUMBER FOR THE RUBBER PIPE WAS 92059-120 WHILE THE SILENCER PART NUMBER REMAINED UN-CHANGED.

OWNER'S HANDBOOK: PART NUMBER 99997-832

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CHAPTER SIX.THE 1976 (K)Z900-A4 STARTING FRAME NO: Z1F-085701 ONWARDS.

1976 BROUGHT A LARGE CHANGE TO ALL KAWASAKI MODELS. A NEW METHOD OF IDENTIFACATION WAS INTRODUCED. ALL MODELS NOW HAD A PREFIX TO DETERMINE THERE INTENDED USE. "KH" INDICATED KAWASAKI HIGHWAY, "KT" INDICATED KAWASAKI TRIAL, "KX" KAWASAKI MOTOCROSS, "KE" KAWASAKI ENDURO AND "Z" INDICATED FOURSTROKE ROADBIKE. EVERYTHING ELSE MADE SENSE EXCEPT THE "Z". PERHAPS KAWASAKI WERE SO PROUD OF THEIR "Z" RANGE THAT THEY DID NOT WANT TO CHANGE IT. THE "KFR900" WOULD NOT HAVE SOUNDED NOWHERE NEAR AS GOOD, WOULD IT ?.AND SO THE FOURTH MODEL IN THE 900 RANGE BECAME THE Z900-A4. THE LAST NUMBER, IN THIS CASE 4, WAS THE NUMBER OF YEARS IN PRODUCTION. IN THE STATES IT WAS KNOWN AS THE "KZ900-A4".JAPANESE PRODUCTION OF THE Z900-A4 STARTED IN OCTOBER 1975 IN READINESS FOR THE 1976 SEASON.KAWASAKI DID NOT JUST CHANGE THE NAME, THE Z900-A4 WAS BESTOWED WITH MANY COSMETIC AND MECHANICAL DIFFERENCES. SOME OF THEM OBVIOUS SOME OF THEM NOT.

FRAME:THE DESIGN OF THE FRAME WAS CHANGED TO ACCEPT MANY MODIFIED FRAME FITTINGS SUCH AS THE BATTERY BOX AND AIR FILTER BOX.NOT ONLY THIS BUT IT WAS ALSO STRENGTHENED WITH HEAVIER GAUGE TUBING IN AN EFFORT TO IMPROVE THE HANDLING. THE BRACKET WHERE ONE COULD ATTACH THE OPTIONAL STEERING DAMPER WAS REMOVED AND IN ITS PLACE, ON EACH SIDE WAS A SMALL THREADED BRACKET WHERE A SMALL ORANGE REFLECTOR COULD BE SCREWED ON FOR THE AMERICAN MARKET.THE BATTERY BOX WAS NOW MOUNTED LOWER IN THE FRAME AND THE BATTERY NOW EXITED FROM UNDERNEATH THE RIGHT HAND SIDE PANEL. A BLACK METAL BRACKET HELD THE BATTERY IN AND THIS ALSO HELD THE BOTTOM SIDE PANEL MOUNTING. THE BATTERY BOX WAS BOLTED BY TWO 6MM BOLTS TO THE FRAME AT THE REAR AND BY TWO MORE 6MM BOLTS AT THE FRONT ATTACHED TO A BLACK METAL STAY WHICH RAN BETWEEN THE TWO REAR ENGINE MOUNTS. THIS ARRANGEMENT HELPED TO BRACE THE FRAME AND THUS STRENGTHEN IT. ALSO ATTACHED TO THIS STAY WAS A SMALL BLACK BRACKET WHICH SUPPORTED THE NEWLY DESIGNED AIR BOX ASSEMBLY.THE TOOL BOX WAS NOW A PLASTIC CASE ALSO UNDERNEATH THE RIGHT SIDE PANEL AND THIS ALSO DOUBLED AS A SIDE PANEL MOUNT. THE TOOL KIT, HOWEVER, COULD ONLY BE REMOVED FROM THE TOP OF THE CASE, PULLED OUT FROM UNDERNEATH THE SEAT.THE ELECTRICAL MOUNTING PLATE WAS NOW RE-POSITIONED TO UNDERNEATH THE LEFT HAND SIDE PANEL AND WAS ATTACHED BY THE USUAL SERIES OF RUBBERS, COLLARS AND 6MM BOLTS.

NEW PART NUMBERS:FRAME:32002-149BATTERY BOX: 32097-039BATTERY STRAP: 32100-020ELECTRICAL BASE PLATE:32129-006BATTERY BOX STAY: 32113-003AIR FILTER STAY: 32105-006TOOLBOX: 32098-024ENGINE MOUNT PLATE: 32030-056 RHENGINE MOUNT PLATE: 32030-055 LH

FRONT SUSPENSION:THE FORK INNER TUBES REMAINED THE SAME BUT THE ALLOY LOWERS WERE MODIFIED. THEY NO LONGER HAD THE BOSS FOR HOLDING THE REFLECTORS AND THEY WERE MARGINALLY LONGER. THE LUGS FOR HOLDING THE BRAKE CALLIPERS WERE ALSO MOVED FURTHER APART AND MODIFIED OIL SEALS AND RUBBER DUST CAPS WERE USED. THE TWO BOTTOM AXLE CLAMPS WERE ALSO MODIFIED.

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THE INTERNAL FORK SPRINGS WERE ALSO MODIFIED TO IMPROVE HANDLING AS WAS THE INTERNAL DAMPING RODS. ALL THESE CHANGES RESULTED IN A MORE COMPLIANT RIDE WITHOUT ANY LOSS IN RIGIDITY. THE LOWER YOKE WAS CHANGED AND NOW NO LONGER HAD THE SMALL 8MM HOLE DRILLED THROUGH IT FOR THE STEERING DAMPER. THE SHAPE OF THE YOKE WAS SLIGHTLY DIFFERENT AND THE WHOLE ASSEMBLY WAS STRENGTHENED.THE TOP YOKE WAS MODIFIED TO ACCEPT RUBBER MOUNTINGS FOR THE RE-DESIGNED CLOCK BRACKET.THE TWO LOWER CHROME YOKE COVERS WERE ALSO CHANGED TO ACCOMMODATE THE NEW SHAPE OF THE BOTTOM YOKE.

NEW PART NUMBERS:FORK ASSY: 44001-175FORK LOWER: 44005-063 LHFORK LOWER: 44006-061 RHFORK SEALS: 44009-024FORK DUST SEALS: 44010-032LOWER YOKE: 44037-098TOP YOKE: 44039-073FORK SPRINGS: 44026-071DAMPER RODS: 44022-027AXLE CLAMPS: 44063-014YOKE COVERS: 44064-025

FRONT WHEEL:THE FRONT HUB OF THE Z900-A4 WAS CHANGED FOR THE ONE THAT WAS ALSO USED ON THE 1976 KH250-B1 AND THE Z750-B1 TWIN. THIS HUB WAS NOW FINISHED IN A NATURAL SILVER FINISH AND NOW ONLY USED FOUR 10MM BOLTS TO HOLD ON THE DISK PLATES INSTEAD OF THE PREVIOUS SIX.THE AMERICAN MODEL WAS STILL ONLY FITTED WITH ONE DISC, SO A CHROME BLANKING PLATE WAS ATTACHED ONTO THE RIGHT HAND SIDE OF THE HUB BY TWO 5MM ZINC PLATED PAN HEAD SCREWS. THE SPEEDOMETER GEARBOX WAS NOW A SEPARATE ITEM AND WAS FINISHED IN AN ALLOY SILVER COLOUR, AND NOW DOUBLED AS A SPACER FOR THE LEFT HAND SIDE OF THE HUB. THE FRONT AXLE ITSELF WAS MODIFIED TO ACCEPT TWO LARGE NUTS, WHICH SCREWED ONTO THE AXLE, ONE ON EACH SIDE. A MODIFIED SPACER WAS ALSO USED ON THE RIGHT HAND SIDE OF THE HUB.THE HUB WAS SMALLER THAN THE ONE USED ON THE Z1 AND SO REQUIRED DIFFERENT ANGLED SPOKES AND CONSEQUENTLY A DIFFERENT RIM. THIS RIM STILL REMAINED A CHROMED 19 INCH ITEM FROM THE TAKISAGO COMPANY.

NEW PART NUMBERS:

FRONT WHEEL ASSY: 41074-047 (COMPLETE ASSY)FRONT HUB ASSY: 41034-040SPOKE INNER: 41027-085 SPOKE OUTER: 41028-084SPEEDO GEARBOX: 41078-008FRONT AXLE: 41068-049AXLE NUTS: 41069-033AXLE SPACER: 41069-032FRONT RIM: 41025-085

INSTRUMENTS:

THE SHAPE OF THE CLOCKS ON THE A4 WAS LEFT UN-CHANGED, BUT THE IDIOT LIGHT CLUSTER WAS MODIFIED.

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A NEW CLOCK MOUNTING BRACKET WAS USED WHICH NOW RUBBER MOUNTED TO THE TOP YOKE INSTEAD OF THE PREVIOUS METHOD OF JUST BOLTS. FOUR CONICAL RUBBERS FITTED INTO TWO ROUND HOLES ON THE TOP YOKE AND THE CLOCK MOUNTING BRACKET PUSHED INTO THESE AND WERE SECURED BY TWO 8MM NUTS AND WASHERS. THIS WAS IN AN EFFORT TO REDUCE VIBRATION TO THE INSTRUMENTS AND HAD BEEN USED WITH SUCCESS ON THE TRIPLE RANGE.THE CENTRAL LIGHT CLUSTER WAS NOW CHANGED SO THAT THE WARNING LIGHTS RAN UPWARDS BETWEEN THE TWO METERS. TWO SEPARATE LIGHTS FOR THE INDICATORS WERE NOW POSITIONED ONE ON EACH SIDE OF THE IGNITION SWITCH. THE SHAPE OF THE BOTTOM PLASTIC COVER WAS CHANGED TO ACCOMMODATE THIS NEW ARRANGEMENT WHILE THE INSTRUMENT WIRING LOOM WAS ALSO MODIFIED.THE COLOUR OF THE SPEEDO AND TACHO FACE WAS CHANGED TO A SLIGHTLY DARKER FINISH WHILE THE BRAKE FAILURE WARNING LIGHT WAS REMOVED FROM THE TACHO AND POSITIONED IN THE IDIOT LIGHT COVER.THE SMALL METAL HOLDER FOR THE IGNITION SWITCH WAS SHORTENED BECAUSE THE WARNING LIGHT COVER WAS NOT AS TALL AS PREVIOUS MODELS.

NEW PART NUMBERS:SPEEDOMETER: 25006-056 (MPH)TACHOMETER: 25016-028CLOCK BRACKET: 25008-045WARNING COVER: 25023-015 TOPWARNING COVER: 25024-006 BOTTOMWIRING LOOM: 25011-049IGNITION SWITCH: 27005-086SWITCH HOLDER: 27019-003METER BRACKET MOUNTING RUBBERS: 92075-080

HANDLEBAR AND CONTROLS:

THE HANDLEBARS ON THE A4 REMAINED THE SAME BUT THE RUBBER HAND GRIPS WERE CHANGED TO A NEW DESIGN THAT WAS FITTED TO ALL 1976 ROAD BIKES.THE LEFT AND RIGHT SWITCHGEAR WERE COSMETICALLY CHANGED BUT THERE FUNCTION REMAINED THE SAME.THE HOLDER FOR THE CLUTCH LEVER WAS MODIFIED TO A STRONGER THICKER ASSY WHICH INCORPORATED A MUCH WIDER BOSS ON THE CLUTCH LEVER.

NEW PART NUMBERS:

LH SWITCHGEAR: 46091-057RH SWITCHGEAR: 46132-024LH HANDLE GRIP: 46075-028RH TWIST GRIP: 46019-038CLUTCH LEVER ASSY: 46076-049 (COMPLETE ASSY)HOLDER: 46094-017LEVER: 46092-022BOLT: 92007-047

MIRRORS:THE A4 MIRRORS WERE COSMETICALLY CHANGED TO A MORE ROUNDED APPEARANCE. THIS MADE THE INTERNAL ADJUSTMENT EASIER.FOR THE FIRST TIME CHROME ITEMS WERE OFFERED ON SOME EUROPEAN MODELS.

NEW PART NUMBERS: 56002-027 BLACKLH MIRROR: 56003-014 CHROMERH MIRROR: 56002-022 CHROME

REAR SUSPENSION:

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THE REAR SHOCK ABSORBERS FITTED TO THE A4 WERE THE SAME FOR ALL MARKETS. THE AMERICAN MODEL NO LONGER HAD REFLECTORS ON THEM.THEY WERE AN ALL CHROME FINISH.

NEW PART NUMBER:SHOCK ABSORBERS: 45014-107

FOOTREST:THE FRONT FOOTREST REMAINED THE SAME BUT THE REAR ITEMS WERE MODIFIED.THE FITTING BRACKETS WERE THE SAME BUT THE RUBBER WAS NOW BONDED ONTO THE STEM AND COULD NOT BE BOUGHT SEPARATELY. THE RUBBER WAS RIBBED AS BEFORE BUT NOW A SMALL KAWASAKI "K" WAS EMBOSSED INTO IT.

NEW PART NUMBER:REAR FOOTREST: 92076-027

GRAB RAIL:

THE GRABRAIL ON THE A4 STAYED THE SAME AS THE Z1, ON AMERICAN AND SOME EUROPEAN MODELS, BUT THE UK MODEL HAD A MODIFIED RAIL WHICH NOW INCORPORATED A BRACKET TO HOLD THE REAR INDICATOR STEMS.NEW PART NUMBER:

GRAB RAIL: 35032-030 (UK)

STANDS:

IN LINE WITH THE STRONGER FRAME, THE SIDE STAND ON THE A4 WAS ALSO STRENGTHENED. THE MAIN STAND ALSO RECEIVED ATTENTION WITH EXTRA WELDING ON THE GUSSETS. THE PART NUMBER FOR THE MAIN STAND HOWEVER, REMAINED THE SAME.

NEW PART NUMBER:

SIDE STAND: 34024-060

FENDERS:

THE FRONT FENDER ON THE A4 REMAINED THE SAME BUT THE REAR ITEM WAS MODIFIED. THE SHORT EXPORT TYPE STAYED THE SAME BUT THE LONG UK ITEM WAS CHANGED TO INCORPORATE TWO SMALL HOLES AT THE BOTTOM OF IT TO ATTACH A CHROME BRACKET AND A SMALL ROUND RED REFLECTOR.THIS BRACKET WAS ATTACHED TO THE FENDER BY TWO 6MM PAN HEAD SCREWS AND SECURED BY 6MM NUTS AND WASHERS.THE SHAPE OF THE FENDER WAS ALSO SLIGHTLY CHANGED TO MAKE IT WIDER AT THE BOTTOM.

NEW PART NUMBERS:

REAR FENDER: 35022-123BRACKET: 28013-010REFLECTOR: 28012-015

REAR BRAKE PANEL:

THE BRAKE PANEL ON THE A4 WAS SLIGHTLY CHANGED COSMETICALLY.THE BRAKE WARNING INDICATOR WAS NOW EMBOSSED INTO THE PLATE ITSELF.

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A NEW MATERIAL WAS ALSO USED TO LINE THE TWO REAR BRAKE SHOES.

NEW PART NUMBERS:REAR SHOE: 41048-016REAR BRAKE PANEL: 42006-062

CHAIN AND SPROCKETS:

FOR THE FIRST TIME AN ALTERNATIVE REAR SPROCKET WAS OFFERED FOR THE 900 RANGE. THE A4 WAS FITTED WITH A 33 TOOTH ITEM AS STANDARD IN THE UK AND MANY OTHER MARKETS WITH ONLY ITALY KEEPING THE PREVIOUS 35 TOOTH SPROCKET.

NEW PART NUMBER:SPROCKET: 42041-161 33 TEETH

TAIL LIGHT:

THE A4 WAS FITTED WITH A SQUARE TAIL LIGHT NOW INSTEAD OF THE PREVIOUS ROUND SHAPE.BECAUSE OF THIS THE TAIL LIGHT BRACKET WAS MODIFIED TO ACCEPT THIS NEW SHAPE. THE LIGHT WAS NOW FITTED TO THE BRACKET WITH ONLY TWO 6MM BOLTS INSTEAD OF THE PREVIOUS THREE.THE AMERICAN MODEL HAD A ROUND REFLECTOR BUILT INTO EACH SIDE OF THE LENS WHILE THE UK MODEL CONFORMED TO LOCAL LAWS BY HAVING THE REFLECTOR ON THE REAR FENDER.

NEW PART NUMBERS:TAIL LIGHT ASSY: 23024-078 (COMPLETE ASSY) UKTAIL LIGHT BRACKET: 23036-048CHROME BACKING: 23027-042TAIL LIGHT LENS: 23026-035

SEAT ASSEMBLY:

THE SEAT ON THE A4 WAS MODIFIED TO INCORPORATE A NEW LOCKING DEVICE. INSTEAD OF THE PREVIOUS LEVER AND CATCH AFFAIR THE A4 USED A SEPARATE LOCK AND A "D" SHAPED BRACKET ATTACHED TO THE BASE OF THE SEAT.THE SEAT COVER ITSELF WAS DECORATED WITH A DIFFERENT PATTERN AND A THICKER MORE COMFORTABLE FOAM WAS FITTED, WHILE THE AMERICAN MODEL STILL HAD NO STRAP FITTED TO IT.THE TWO SEAT PINS WERE MODIFIED TO AN "L" SHAPE TO MAKE THEM HARDER TO REMOVE WITH THE SEAT LOCKED. A SMALL THEFT DETERRENT BUT AT LEAST THEY WERE AT LAST THINKING ABOUT IT. THE HINGES WERE ALSO MODIFIED TO ASSIST THIS MOVE.THE LOCK ITSELF WAS BOLTED TO THE FRAME WITH A SINGULAR 6MM BOLT AND THE FACE OF IT PROTRUDED JUST ABOVE THE REAR OF THE LEFT HAND SIDE PANEL.

NEW PART NUMBERS:

SEAT ASSY: 53001-125 UKSEAT LOCK: 27030-005SEAT LOCK BRACKET: 53056-002SEAT LOCK PLATE: 53058-003SEAT PINS: 53011-008SEAT HINGE: 53009-037 FRONTSEAT HINGE: 53009-017 REAR

ELECTRICAL EQUIPMENT:

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THE BIG MODIFICATION FOR 1976 WAS THE USE OF A THREE FUSE SYSTEM INSTEAD OF THE PREVIOUS SINGLE SYSTEM. A BLACK PLASTIC FUSE BOX WAS RUBBER MOUNTED TO THE BATTERY BOX AND CONTAINED THREE IN LINE FUSES. A SMALL LEAD RAN FROM THIS TO CONNECT TO THE MODIFIED MAIN WIRING LOOM.TWO MORE SAFETY ITEMS WERE USED ON THE A4 FOR THE FIRST TIME. THE FIRST WAS A HAZARD WARNING LIGHT SYSTEM, WHICH COULD OPERATE THE FOUR FLASHERS AT ONCE. A PLUNGER TYPE SWITCH WAS MOUNTED TO A BRACKET WHICH IN TURN MOUNTED TO TWO OF THE 8MM HANDLEBAR CHROME BOLTS. THIS WAS CONSIDERED TO BE A BIT OF AN EYE SORE AND MANY OWNERS SOON REMOVED THE UNSIGHTLY SWITCH. A SMALL RELAY TO CONTROL THE HAZARD SYSTEM WAS BOLTED TO THE BATTERY BOX AND WIRED TO THE MAIN LOOM. THIS ALLOWED THE SYSTEM TO BE OPERATED WITHOUT THE IGNITION SWITCH TURNED ON.THE OTHER ITEM WAS AN AUDIBLE INDICATOR SYSTEM. THIS CONSISTED OF A SMALL ELECTRICAL BUZZER BOLTED TO THE BOTTOM OF THE HEADLAMP SHELL. WHEN EITHER OF THE INDICATORS WAS USED THE BUZZER OMITTED A BUZZING NOISE, NOT UNLIKE THE NOISE FROM A PELICAN CROSSING. WHEN RAIN ENTERED THE BUZZER, WHICH GIVEN THE ENGLISH WEATHER, WAS FREQUENTLY, THE NOISE TURNED TO ONE THAT A STRANGLED CAT MAY MAKE !!. NEEDLESS TO SAY, THE BUZZERS WERE QUICKLY REMOVED BY OWNERS AND DEALERS. IT WAS ALSO NOTED THAT BLIND PEOPLE MAY HAVE CONFUSED THEM WITH THE NOISE FROM PELICAN CROSSINGS, CAUSING CONCERN TO MANY.A SLIGHTLY DIFFERENT RECTIFIER WAS FITTED TO THE A4 AND THE REGULATOR WAS ALSO MODIFIED AND FITTED WITH A LONGER LEAD TO ACCOMMODATE THE CHANGE IN POSITION OF THE BATTERY BOX. KAWASAKI WERE STILL TRYING TO SOLVE THE PROBLEM OF BLOWING HEADLAMPS.THE TWO IGNITION COILS WERE MODIFIED AND NO LONGER HAD THE SMALL CLIPS WITH THE INDENT NUMBERS ON THEM. INSTEAD THE LEADS NOW HAD A SMALL PIECE OF SILVER TAPE ON THEM WITH THE RELEVANT NUMBERS ON THEM.THE MAIN WIRING LOOM ALONG WITH THE CENTRE LOOM WAS MODIFIED TO TAKE INTO CONSIDERATION ALL THE NEW EQUIPMENT.THE HORN ASSEMBLY WAS RE-DESIGNED AND COSMETICALLY CHANGED WHILE THE BATTERY WAS CHANGED FOR A SMALLER 10AMP ITEM THAT WOULD FIT INTO THE NEW BATTERY BOX.THE OIL PRESSURE SWITCH AND THE NEUTRAL SWITCH WERE MODIFIED TO TAKE A PUSH ON CONNECTOR INSTEAD OF THE PREVIOUS SCREW ON TYPE. BECAUSE THE WIRES FOR THESE TWO SWITCHES CAME WITH THE ALTERNATOR, THE WHOLE OF THE ALTERNATOR ASSEMBLE WAS MODIFIED. INCLUDED WITH THIS MODIFICATION WAS AN IMPROVED CAP FOR THE OIL PRESSURE SWITCH WHICH WAS NOW MADE OUT OF PLASTIC INSTEAD OF THE PREVIOUS RUBBER, WHICH EASILY BROKE UP.

NEW PART NUMBERS:WIRING LOOM: 26001-135EARTH LEAD: 26010-043LIVE LEAD: 26010-042CENTRE LOOM: 26002-057HORN ASSY.: 27003-055HAZARD SWITCH: 27014-008SWITCH BRACKET: 32060-019SWITCH RELAY: 21066-024SWITCH REGULATOR: 21066-026FUSE BOX: 26004-035AUDIBLE BUZZER: 27040-002NEUTRAL SWITCH: 13151-022OIL PRESSURE SWITCH: 16144-004ALTERNATOR ASSY: 21076-023IGNITION COIL 1+4: 21121-081IGNITION COIL 2+3: 21121-082REGULATOR: 21066-025RECTIFIER: 21061-024BATTERY: 26012-042 (YUASA YB10L-A2)

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AIR CLEANER ASSEMBLY:

ONE OF THE PROBLEMS WITH THE Z1 WAS THE ONE PIECE AIR BOX. WHEN THE INLET RUBBERS SHRANK WITH AGE IT MEANT THAT A COMPLETE AIR BOX WAS REQUIRED TO RECTIFY THE RESULTING PROBLEM. TO COUNTER ACT THIS KAWASAKI PRODUCED A MODIFIED AIR BOX FOR THE A4 WHICH HAD REMOVABLE INLET RUBBERS. THIS NEW BOX USED A DIFFERENT FILTER ELEMENT AND ALSO MADE USE OF A SECONDARY NOISE INDUCTION SILENCER. THIS WAS A SIMPLE PLASTIC TUBE CONTAINING ANOTHER FILTER ELEMENT WHICH ATTACHED TO THE BACK OF THE MAIN AIR BOX. A BLACK METAL CLAMP ENSURED A SAFE FIT. THE AIR BOX LID USED ON THE A4 WAS NOW A SOLID ITEM UNLIKE THE PREVIOUS Z1 GRILL.BECAUSE OF THE SHAPE OF THIS NEW AIR BOX THE PLASTIC SIDE PANELS HAD TO BE RE-DESIGNED TO FIT SNUGLY AROUND IT.

NEW PART NUMBERS:AIR BOX: 11011-054INLET RUBBER: 11015-050 #1INLET RUBBER: 11015-051 #2+3INLET RUBBER: 11015-052 #4AIR FILTER: 11013-054SILENCER: 11016-008SILENCER CLAMP: 92037-106AIR BOX LID: 11012-070DRAIN TUBE: 92059-124

EXHAUST SYSTEM:

ALTHOUGH THE SHAPE OF THE MUFFLERS ON THE A4 WERE NOT CHANGED, THE INTERNALS WERE. THE INTERNAL BAFFLES WERE MODIFIED TO INCREASE THE EFFICIENCY OF THE SILENCING. THIS WAS TO BRING THEM IN LINE WITH THE TOUGH NEW EMISSION LAWS OF 1976. THE EXTERNAL BAFFLE WAS ALSO MODIFIED AND WAS NOT NOW A REMOVABLE ITEM.THE STAMPING ON THE SILENCERS WAS CHANGED TO INCLUDE THE NUMBERS "76" TO CONFIRM THAT THEY CONFORMED.

NEW PART NUMBERS:MUFFLER: 18001-227 LH UPPERMUFFLER: 18001-228 LH LOWERMUFFLER: 18001229 RH LOWERMUFFLER: 18001-230 RH UPPER

FRONT BRAKE ASSEMBLY:

PERHAPS THE BIGGEST IMPROVEMENT ON THE A4 WAS IN THE BRAKING DEPARTMENT. MOST MODELS WERE NOW FITTED WITH TWO DISKS AS STANDARD INSTEAD OF THE PREVIOUS ONE.THE AMERICAN MODEL, HOWEVER, WAS STILL ONLY FITTED WITH ONE AS STANDARD. HOWEVER AN OPTIONAL TWIN SET UP WAS OFFERED AS A GENUINE PART FROM DEALERS.THE DISK WERE NOW BOLTED TO THE FRONT WHEEL HUB BY FOUR ZINC PLATED 10MM BOLTS AND SECURED WITH TWO TAB WASHERS. A CHROME THIN PLATE WAS UTILISED ON EACH SIDE OF THE HUB TO SMARTEN UP THE ASSEMBLY.THE DISKS ON THE TWIN SET UP WERE TWO THIN 4.5MM THICK ITEMS WHICH HELPED TO REDUCE UN-SPRUNG WEIGHT, WHILE THE SINGLE SET UP USED ONE 6MM THICK ITEM.THE CALLIPERS WERE A NEW DESIGN THAT WAS BEING USED ON ALL 1976 ROAD BIKES. THE BODIES OF THE CALLIPERS WERE NOW A ONE PIECE UNIT WHICH USED TWO 10MM HEXAGON BOLTS INSTEAD OF ALLEN BOLTS TO HOLD THE SLIDING PAD HOLDER. THE USUAL ARRANGEMENT OF RUBBERS AND O`RINGS WAS USED BUT THE PADS THEMSELVES WERE OF A DIFFERENT DESIGN AND OF AN IMPROVED MATERIAL.THE BRAKE JUNCTION BOX NOW HAD AN EXTRA OUTLET ON IT, TO WHICH THE SECOND FLEXIBLE HOSE ATTACHED TO. THIS HOSE RAN DOWN TO ANOTHER SHAPED METAL PIPE AND

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ATTACHED DIRECTLY TO THE SECOND CALLIPER. A CHROME BRACKET WAS SANDWICHED BETWEEN THE FENDER AND THE RIGHT HAND FORK LOWER TO HOLD THIS HOSE IN PLACE.THE MASTER CYLINDER WAS FITTED WITH A LARGER PISTON ASSEMBLY, SO THAT IT COULD COPE WITH THE EXTRA FLUID REQUIRED FOR THE SECOND CALLIPER. THE CYLINDER WAS STAMPED UNDERNEATH WITH THE LEGEND "5/8" WHICH WAS THE BORE SIZE OF THE CHAMBER.THIS SECOND BRAKE TRANSFORMED THE A4 INTO A FAR BETTER MOTORCYCLE THAN THE Z1 AND BECAME THE INDUSTRY STANDARD ON ALL JAPANESE MOTORCYCLES.SO WHY DID THE AMERICAN MODEL ONLY GET ONE DISK ?. PERHAPS THE LOWER SPEED LIMITS IN THE STATES MEANT THAT THE RIDERS OVER THERE DID NOT GO FAST ENOUGH TO WARRANT THE EXTRA BRAKING POWER. !!.OR PERHAPS KAWASAKI JUST WANTED TO EXTRACT A FEW MORE DOLLARS FROM THEM FOR THE OPTIONAL SECOND BRAKE KIT. !!

NEW PART NUMBERS:FRONT DISK: 41080-007 (TWIN DISK)FRONT DISK: 41080-005 (SINGLE)CALLIPER: 43041-018 LHCALLIPER: 43041-019 RHCHROME PLATE: 41042-014 LHCHROME PLATE: 41042-015 RHDISK BOLTS: 92001-158TAB WASHERS: 92088-023CALLIPER BOLTS: 92007-032MASTER CYLINDER: 43015-025JUNCTION BOX: 43075-002BRAKE PIPE: 43059-011 RUBBERBRAKE PIPE: 43060-023 LH METALBRAKE PIPE: 43060-024 RH METALBRACKET: 43063-001 RH

BODY WORK:DIAMOND DARK GREEN AND DIAMOND BROWN.

KAWASAKI DID NOT REALLY WANT TO CHANGE THE SHAPE OF THEIR FLAGSHIP, BUT THE MODIFIED AIR BOX AND SQUARE TAIL LIGHT MEANT SOME CHANGES WERE NECESSARY. THE FUEL TANK WAS MADE SLIGHTLY WIDER AND A NEW LOCKING PETROL CAP WAS USED. THIS CAP WAS ANOTHER PART WHICH KAWASAKI USED ON MANY DIFFERENT MODELS THROUGH THE YEARS. ALTHOUGH IT NEEDED A KEY TO UNDO IT, IN REALITY ANYTHING REMOTELY RESEMBLING A KEY WOULD DO. STILL, THIS WAS ANOTHER SIGN THAT THE JAPANESE WERE AT LAST WAKING UP TO THE PROBLEMS OF SECURITY.A MODIFIED FUEL TAP WAS FITTED WHICH USED AN IMPROVED INTERNAL ROUTING OF THE PETROL RESULTING IN LESS LEAKS.THE TWO COLOUR OPTIONS NOW OFFERED WERE GREEN OR BROWN. THE GREEN WAS A MUCH PREFERRED CHOICE OF MANY OWNERS.A GOLD AND A LIGHTER GREEN PINSTRIPE ADORNED THE GREEN OPTION WHILE A GOLD AND A RED PINSTRIPE ADORNED THE BROWN OPTION. ONCE AGAIN THE SIDE PANELS WERE LEFT JUST IN THE BASE COLOUR.THE PANELS THEMSELVES WERE CHANGED SLIGHTLY IN SHAPE TO ACCOMMODATE THE NEWLY DESIGNED AIR BOX ASSEMBLY. THE EMBLEMS ON THE PANELS WERE CHANGED AND NOW ONLY READ "Z900". THE AMERICAN MODELS READ "KZ900". THESE WERE BLACK PLASTIC BADGES WITH WHITE NUMBERS SURROUNDED IN CHROME. THE NUMBER OF CLIPS HOLDING THEM TO THE PANELS WAS REDUCED TO JUST TWO EACH SIDE.THE TAIL PIECE WAS SLIGHTLY ALTERED IN SHAPE TO ACCOMMODATE THE SQUARE TAIL LIGHT ASSEMBLY AND BECAUSE OF THIS, THE INNER PLASTIC TRAY WAS ALSO ALTERED.KAWASAKI OFFERED FOR THE A4, A TOUCH UP PAINT IN A SMALL 1/12 LITRE TIN. THIS COULD BE USED WITH A BRUSH OR THINNED 50/50 AND USED IN A SPRAY GUN.

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NEW PART NUMBERS:FUEL TANK: 51001-107-3M GREENFUEL TANK: 51001-107-3N BROWNFUEL CAP: 51048-012FUEL TAP: 51023-055SIDE COVER: 36001-054-3M LH GREENSIDE COVER: 36001-054-3N LH BROWNSIDE COVER: 36007-051-3M RH GREENSIDE COVER: 36007-051-3N RH BROWNEMBLEM: 56018-238 Z900EMBLEM: 56018-238 KZ900TAIL FAIRING: 53043-013-3M GREENTAIL FAIRING: 53043-013-3N BROWNCASE: 32098-018PAINT: 56019-108-3M GREENPAINT: 56019-108-3N BROWN

TOOLKIT AND HANDBOOK:

THE TOOLKIT ON THE A4 WAS CHANGED DUE TO THE FACT THAT THE ALLEN KEY REQUIRED FOR THE CALLIPER BOLTS ON THE Z1 MODEL WAS NOT NOW NEEDED. THE KIT CONTAINED THE REST OF THE TOOLS OF THE PREVIOUS MODELS.

TWO OWNER HANDBOOKS WERE PRODUCED, ONE FOR THE US MODEL AND ONE FOR THE EUROPEAN MARKET. THE COVER OF BOTH MANUALS WAS FINISHED IN A BLUE COLOUR WITH A PICTURE OF THE RELEVANT MODEL ON IT.

NEW PART NUMBERS:

TOOL KIT: 56007-049HANDBOOK: 99997-844-00 USHANDBOOK: 99997-671 EUROPE

ENGINE CHANGES:

THE ENGINE IN THE Z900 REMAINED BASICALLY THE SAME AS THE PREVIOUS Z1-B MODEL. NO MODIFICATIONS WERE DEEMED NECESSARY.HOWEVER, KAWASAKI IN AN EFFORT TO INCREASE IMPROVED MID RANGE PERFORMANCE, DECIDED TO FIT THE Z900 WITH SMALLER 26MM MIKUNI CARBS.THIS DID ROB THE BIKE OF A FEW HORSEPOWER BUT MADE FOR A MUCH MORE REFINED RIDE. THE NEW CARBS HAD IMPROVED CHOKES AND THE LINKAGES, CONNECTING THE FOUR SLIDES TOGETHER, WERE VASTLY IMPROVED RESULTING IN A SMOOTHER THROTTLE RESPONSE.ADJUSTMENT NOW MEANT THE REMOVAL OF THE FOUR CARB TOPS TO GAIN ACCESS TO THE ADJUSTER SCREWS BUT THIS WAS A SMALL PRICE TO PAY FOR THE MUCH IMPROVED THROTTLE OPERATION.THE CARB TOPS WERE NOW A TALLER DESIGN AND HELD ON BY THREE 4MM SCREWS INSTEAD OF THE PREVIOUS TWO.

NEW PART NUMBERS:

CARBURETTOR ASSEMBLE: 16001-255 MIKUNI 26MM.

FOR AMERICA, KAWASAKI PRODUCED AN OPTIONAL NEEDLE JET FOR THESE CARBS TO HELP IMPROVE FUEL CONSUMPTION. INSTEAD OF THE STANDARD 0.6 JET, A 0.4 ITEM WAS PRODUCED. THIS WAS FITTED TO CUSTOMERS BIKES ONLY IF THE OWNER COMPLAINED OF

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POOR FUEL ECONOMY. THE PART NUMBER FOR THIS JET WAS 16017-1003. IT WAS NOT, HOWEVER, AVAILABLE FOR EUROPEAN MODELS.

A SERVICE BULLETIN WAS SENT OUT TO DEALERS IN MARCH 1976 INFORMING THEM THAT FROM ENGINE NUMBER Z1E-089122, THE CRANKCASES WERE MODIFIED TO INCLUDE A SMALL CUT OUT SLOT ON EACH SIDE OF THE CYLINDER BARREL JOINT, WHICH COULD BE USED AS A PRY POINT WHEN REMOVING THE CYLINDER BARRELS. THE PART NUMBER FOR THE MODIFIED CASES REMAINED THE SAME AT 14001-052-2J.

IN APRIL OF 1976 ANOTHER BULLETIN WAS SENT OUT TO UK DEALERS WARNING THAT THERE WAS A RISK OF THE BOLTS HOLDING THE REAR RED REFLECTOR ONTO THE REAR FENDER TOUCHING THE REAR TYRE CAUSING PUNCTURES. THIS ONLY HAPPENED WHEN THE WHEEL WAS ADJUSTED RIGHT BACK DUE TO CHAIN WEAR.THE SOLUTION WAS TO SHORTEN THE TWO 6MM BOLTS OR TO REVERSE THEM .STRANGELY ENOUGH, KAWASAKI UK REFUSED TO REPLACE ANY DAMAGED TYRES UNDER WARRANTY EVEN THOUGH IT WAS THERE FAULT.ON MODELS WITH THE SHORT REAR FENDER THIS WAS NOT A PROBLEM.

LATER THAT YEAR, DEALERS WERE INFORMED THAT THE VOLTAGE RECTIFIER HAD YET AGAIN BEEN MODIFIED, STILL IN AN EFFORT TO IMPROVE THE TROUBLESOME CHARGING SYSTEM. THE NEW PART NUMBER WAS 21061-1002.

IN OCTOBER 1976 A CLOSE RATIO GEARBOX WAS MADE AVAILABLE TO OWNERS. THIS SET OF GEARS WAS BOUGHT MAINLY BY PRODUCTION RACERS AND CONSISTED OF TEN MODIFIED GEARS. THE PART NUMBER FOR THE GEARBOX WAS 13254-001 AND THE PRICE AT THIS TIME WAS £67.58. KAWASAKI WARNED DEALERS NOT TO FIT THIS GEARBOX INTO THE NEWLY ANNOUNCED Z1000 MODEL BECAUSE OF THE INCREASED TORQUE CHARACTERISTICS OF THIS NEW 1015CC ENGINE MADE IT UNSUITABLE.THE NEW RATIOS WERE:

1ST GEAR 2.50 46/162ND GEAR 1.95 37/193RD GEAR 1.59 35/224TH GEAR 1.38 29/215TH GEAR 1.26 29/23

THE KZ900-A4, PRODUCED FOR THE AMERICAN MARKET WAS UNIQUE IN THAT IT WAS ACTUALLY MADE, OR RATHER ASSEMBLED, ON THE PRODUCTION LINE OF THE LINCOLN PLANT IN NEBRASKA. THIS PLANT HAD PREVIOUSLY PRODUCED THE Z400 TWIN MODEL IN EARLY 1975. THIS WAS A FIRST FOR A JAPANESE COMPANY AND GOT THE BIKES RIGHT WHERE KAWASAKI WANTED THEM, IN THE WORLDS BIGGEST MARKET PLACE FOR MOTORCYCLES.ENGINE UNITS WERE IMPORTED FROM JAPAN AND FITTED INTO FRAMES ON THE PRODUCTION LINE. EVENTUALLY MORE PARTS WERE TO BE SOURCED IN THE STATES LEADING TO A "MADE IN THE USA" MOTORCYCLE. KAWASAKI WERE SO CONFIDENT OF THE 900 RANGE THAT THEY INVESTED OVER $20 MILLION IN THE LINCOLN PLANT.PRODUCTION OF THE KZ900 AT LINCOLN STARTED IN JUNE 1975 IN READINESS FOR THE 1976 SEASON. 9200 UNITS WERE PRODUCED IN 1975 WITH ANOTHER 12144 PRODUCED IN 1976. THIS WAS ABOUT 60% OF THE TOTAL Z900-A4 PRODUCTION, PROVING JUST EXACTLY WHERE KAWASAKI THOUGHT THEIR LARGEST MARKET WAS.MANY KZ900`S HAVE FOUND THEIR WAY ALL OVER THE WORLD, SOME BEING CONVERTED TO EUROPEAN SPEC. THE MAIN DOWNFALL BEING THAT SINGLE DISK SET UP AND THE SOMETIMES DUBIOUS CUSTOM ACCESSORIES THAT WERE FITTED.

ALL IN ALL THE Z900-A4 WAS PROBABLY THE BEST OF THE 900 SERIES AND WAS CERTAINTY THE BEST SELLER, BUT IT IS STILL CONSIDERED THE RUT OF THE LITTER AND DOES NOT COMMAND AS MUCH ATTENTION OR VALUE OF THE EARLIER MODELS. HOWEVER, ASK ANY MOTORCYCLIST TO NAME A KAWASAKI 900 AND HE WILL MOST CERTAINLY QUOTE THE "Z900".

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CHAPTER SEVEN

THE KZ900-BI LTD: STARTING FRAME NO: KZ900B-500011 ONWARDS

IT HAD BECOME INCREASINGLY OBVIOUS TO KAWASAKI IN AMERICA THAT MOST OWNERS WERE NOT QUITE HAPPY WITH THEIR STANDARD Z1 AND A WHOLE NEW BUSINESS HAD BEGUN SUPPLYING CUSTOM AFTER MARKET PARTS FOR THE Z-RANGE.KAWASAKI AMERICA, NOT TO BE OUTDONE, DECIDED TO PRODUCE A LIMITED EDITION 900 TO SATISFY THERE CUSTOMERS NEEDS.KAWASAKI AMERICA EXECUTIVE WAYNE MOULTON THOUGHT THAT THEY COULD PERHAPS PERSUADE SOME OF THE DIE HARD HARLEY RIDERS AWAY FROM THEIR "CHOPPERS" ON TO A "RICE BURNER" WITHOUT LOSING THEIR STREET CRED.! THE RESULTING KZ900-B1 LTD WAS THE FIRST FOR A JAPANESE COMPANY AND STARTED THE BALL ROLLING FOR ALL THE MAJOR MANUFACTURERS TO PRODUCE A CUSTOM TYPE BIKE.THE IDEA WAS SIMPLE. A STANDARD BIKE WAS STRIPPED ON THE PRODUCTION LINE AND FITTED WITH ALL THE BOLT ON TRICK BITS THAT OWNERS WOULD NORMALLY FIT AFTERWARDS. A LIMITED RUN OF JUST 2000 BIKES WERE BUILT AND THE DEMAND FOR THEM PROVED OVER WHELMING. KAWASAKI WERE ONCE AGAIN ON TO A WINNER.THE 900 LTD WAS OFTEN IMITATED BUT NEVER EQUALLED. EVEN KAWASAKI WENT ON TO PRODUCE A 250, 305, 400, 440, 550, 650, 750, 1000, AND 1100 CC VERSIONS OF THE FAMOUS "LTD" RANGE.BY THE MID EIGHTIES THE TREND HAD SLOWED DOWN SOMEWHAT BUT RECENTLY THE CUSTOM CRUISER IMAGE HAS MADE A MASSIVE COMEBACK WITH KAWASAKI PLAYING A MAJOR ROLE WITH THEIR VULCAN, VN, EN AND DRIFTER RANGE.

HANDLEBARS:A WIDER, WESTERN, PULL BACK STYLE SET OF HANDLEBARS WERE FITTED TO THE LTD. THESE WERE HEAVILY CHROMED ITEMS AND GIVE THE RIDER A MORE RELAXED RIDING POSITION.

NEW PART NUMBER: HANDLEBARS: 46003-037

INSTRUMENTS:THE BOTTOM CLOCK COVERS WERE NOW CHROMED INSTEAD OF THE PREVIOUS BLACK ITEMS.

NEW PART NUMBERS:COVER SPEEDO: 25012-023COVER TACHO: 25012-024

HEADLAMP:

THE HEADLAMP SHELL WAS NOW CHROMED INSTEAD OF BLACK.THE HEADLAMP ASSEMBLY WAS ONLY FOR AMERICAN FITMENT AND WAS THE USUAL SEALED BEAM TYPE.

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NEW PART NUMBERS:HEADLAMP SHELL: 23005-055HEADLAMP UNIT: 23003-017

FORK ASSEMBLY:THE FORKS THEMSELVES REMAINED THE SAME BUT THE HEADLAMP BRACKETS AND RELEVANT FITTINGS WERE REMOVED AND IN THERE PLACE WAS A SMALL BLACK METAL BRACKET WHICH BOLTED TO THE TOP YOKE. THIS WAS SANDWICHED BETWEEN THE YOKE AND THE CLOCK BRACKET, AND WRAPPED ROUND TO HOLD THE HEADLAMP SHELL. TWO CHROME 10MM BOLTS WENT THROUGH THIS BRACKET AND THEN THROUGH A SERIES OF RUBBERS AND COLLARS AND THEN INTO THE HEADLAMP SHELL. TWO 10MM NUTS THEN TIGHTENED EVERYTHING UP.THE FORK LEG BOTTOMS WERE REVERSED SO THAT THE CALLIPERS COULD BE MOUNTED ONTO THE REAR OF THEM. THIS WAS BELIEVED TO IMPROVE WET WEATHER BRAKING.

NEW PART NUMBERS:FORK ASSY: 44001-195HEADLAMP BRACKET: 23064-030BOLTS: 92007-024RUBBERS: 23066-022 OUTERRUBBERS: 23066-021 INNERCOLLARS: 23052-010WASHERS: 411D1000NUTS: 315B1000

FRONT WHEEL:THE LTD WAS FITTED WITH A 19 INCH SEVEN SPOKE MORRIS CAST ALUMINIUM WHEEL, MODIFIED TO ACCEPT THE STANDARD KAWASAKI DISKS AND AXLE. IT WAS SHOD WITH A GOODYEAR EAGLE ML90 GT TYRE. THE WHEEL WAS FINISHED IN BLACK WITH POLISHED EDGES TO THE RIM AND SPOKES.

NEW PART NUMBERS:FRONT WHEEL: 41087-001FRONT TYRE: 41021-071ADAPTER PLATE: 41088-001 LHADAPTER PLATE: 41080-002 RHDISK MOUNTING BOLTS: 92001-179

FRAME:THE FRAME ON THE LTD WAS MODIFIED TO ACCEPT THE REAR DISK BRAKE MASTER CYLINDER. THIS MODIFICATION CONSISTED OF A SMALL BRACKET WELDED TO THE FRAME TUBE ABOVE THE REAR BRAKE PEDAL SHAFT. THE MASTER CYLINDER WAS SECURED TO THIS BRACKET BY TWO 8MM ZINC PLATED BOLTS.NEW PART NUMBER:FRAME: 32002-154

FRONT FENDER:THE LTD WAS FITTED WITH A CHROME FENDER BUT IT WAS SHORTER THAN THE STANDARD ONE TO GIVE IT THAT CUSTOM LOOK.NEW PART NUMBER:FRONT FENDER: 35003-019

FRONT BRAKE:TWO DISK BRAKES WERE NOW FITTED AS STANDARD AND BECAUSE OF THIS, A LARGER CAPACITY MASTER CYLINDER WAS REQUIRED.

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THE TWO METAL BRAKE PIPES CONNECTING TO THE CALLIPERS NOW HAD TO BE SHORTER BECAUSE OF THE NEW BRAKE SET UP.A LONGER SPEEDO CABLE WAS ALSO NEEDED TO ROUTE AROUND THE LEFT HAND CALLIPER BODY.NEW PART NUMBERS:MASTER CYLINDER: 43015-018LH BRAKE PIPE: 43060-025RH BRAKE PIPE: 43060-026SPEEDO CABLE: 54001-1010

MIRRORS:THE STEMS ON THE LTD MIRRORS WERE SHORTENED TO GIVE A NEATER APPEARANCE. THEY WERE HOWEVER, STILL FINISHED IN BLACK.NEW PART NUMBER:MIRROR: 56002-028

FRONT INDICATORS:

THE FRONT INDICATORS WERE NOW FASTENED TO THE HANDLEBARS AND INSTEAD OF THE LARGE Z1 TYPE, THE SMALLER ITEMS SIMILAR TO THE KH250 LAMPS WERE USED. THESE WERE FITTED WITH DUAL FILAMENT BULBS TO ACT AS RUNNING LIGHTS.NEW PART NUMBERS:INDICATOR: 23040-054BRACKET: 23051-1013 TOPBRACKET: 23051-1004 BOTTOMMOUNTING RUBBER: 23066-003EARTH LEAD: 26011-061WIRE COVER: 26009-004

CABLES:

BECAUSE OF THE HIGHER BARS, LONGER CLUTCH AND THROTTLE CABLES WERE NEEDED.

NEW PART NUMBERS:CABLE THROTTLE: 54012-142 OPENCABLE THROTTLE: 54012-135 CLOSECABLE CLUTCH: 54011-089

STANDS:BECAUSE OF THE USE OF LOW SLUNG EXHAUST, THE MAIN STAND NEEDED TO BE REMOVED.BECAUSE OF THIS, A STRONGER, SHORTER SIDE STAND WAS FITTED.NEW PART NUMBER:SIDE STAND: 34024-065

SWITCHGEAR:BECAUSE THE LTD WAS ONLY FOR THE AMERICAN MARKET, THE HANDLE BAR SWITCH GEAR WAS ONLY OFFERED IN ONE TYPE.THE HAZARD WARNING SWITCH, PREVIOUSLY BOLTED ONTO THE HANDLEBAR MOUNTINGS, WAS REMOVED ON THE LTD TO IMPROVE IT'S SLEEK LINES.NEW PART NUMBERS:SWITCH: 46091-044 LHSWITCH: 46132-021 RH (USA)SWITCH: 46132-022 RH (CANADA)

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REAR WHEEL:

THE REAR WHEEL WAS ONCE AGAIN A SEVEN SPOKE MORRIS ITEM FINISHED IN BLACK WITH POLISHED EDGES ON THE OUTER RIM AND SPOKES. HOWEVER INSTEAD OF THE USUAL 18 INCH ITEM, IT WAS FITTED WITH A WIDE 16 INCH ONE. THIS ALLOWED THE USE OF A FAT REAR TYRE WHICH WAS ALL THE FASHION AT THAT TIME.THE TYRE FITTED WAS A GOODYEAR EAGLE MT90-16T.A NEW SPROCKET CARRIER AND SPACERS WERE REQUIRED IN ORDER TO FIT THIS WHEEL INTO THE KAWASAKI CHASSIS.THE REAR SPROCKET WAS ALSO MODIFIED IN ORDER TO FIT THE SMALLER WHEEL. THIS SPROCKET WAS NOW A DIFFERENT DESIGN WITH 35 TEETH, HOWEVER THE REAR DRIVE CHAIN REMAINED THE SAME AT 92 LINKS.NEW PART NUMBERS:REAR WHEEL: 41087-002REAR TYRE: 41021-072INNER TUBE: 41022-047SPROCKET CARRIER: 42008-039CUSH DRIVE RUBBER: 42014-031COUPLING HOUSING: 41088-006SPACER: 42036-032SPACER: 41039-036SPACER: 42032-061SPACER: 42036-027REAR SPROCKET: 42041-171 35TTAB WASHERS: 92088-031 (FOR SPROCKET BOLTS)

REAR BRAKE:INSTEAD OF THE PREVIOUS DRUM BRAKE, THE LTD WAS FITTED WITH A REAR DISK BRAKE. THIS WAS MORE OF A COSMETIC CHANGE THAN FUNCTIONAL, BECAUSE THE OLD DRUM BRAKE WAS MUCH BETTER. HOWEVER, FASHION DICTATED THE CHANGE.A 277 MM DISK PLATE WAS BOLTED TO THE REAR MORRIS WHEEL VIA AN ADAPTER PLATE AND FOUR 10MM BOLTS. TWO TAB WASHERS SECURED THESE BOLTS IN POSITION. A SINGLE PISTON CALLIPER WAS FITTED ONTO A HOLDER PLATE WHICH THE REAR AXLE RAN THROUGH. A CHROME TORQUE ARM RAN FROM THE CALLIPER BRACKET DOWN TO THE REAR SWINGING ARM WHERE IT WAS SECURED AT EACH END BY A 12 MM BOLT. THIS TORQUE ARM WAS NOW FASTENED ON TOP OF THE SWING ARM UNLIKE PREVIOUS DRUM BRAKE MODELS WHICH WERE FASTENED UNDERNEATH.A REAR MASTER CYLINDER WAS BOLTED TO THE RIGHT HAND FRAME TUBE AND CONNECTED TO THE REAR CALLIPER BY A RUBBER HYDRAULIC PIPE. THIS PIPE RAN THROUGH A SMALL METAL LOOP ON THE SWING ARM AND WAS PROTECTED BY A RUBBER GROMMET. THE REAR BRAKE PEDAL AND RETURN SPRING WERE MODIFIED FROM THE STANDARD Z900 ITEM TO ACCEPT A METAL PUSH ROD WHICH ACTIVATED THE PISTON IN THE MASTER CYLINDER. THE ROD WAS CONNECTED TO THE BRAKE PEDAL BY A SHOULDERED 8MM BOLT AND CASTLE NUT. THE MASTER CYLINDER WAS SIMILAR TO THE FRONT ONE USING A METAL SCREW ON CAP TO ENABLE ACCESS TO THE FLUID RESERVOIR. NEW PART NUMBERS:REAR CYLINDER: 43015-036PUSH ROD: 43010-022CONNECTOR BOLT: 92003-210CASTLE NUT: 321B0800REAR DISK PLATE: 41080-012ADAPTER PLATE: 41088-006TAB WASHERS: 92088-032REAR CALLIPER: 43041-024REAR BRAKE PIPE: 43059-030REAR BRAKE PEDAL: 43001-073

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RETURN SPRING: 43005-039TORQUE ARM: 43007-047BOLT: 92003-225 12MMBOLT: 92003-197 12MMNUT: 42045-021 12MMRUBBER: 43064-007

REAR SWINGING ARM:BECAUSE OF THE USE OF A REAR DISK BRAKE THE SWING ARM ON THE LTD HAD TO BE REDESIGNED. THE BRACKET WHICH HELD THE TORQUE ARM HAD TO BE MOVED FROM THE UNDERNEATH OF THE ARM TO THE TOP OF IT.A CHROME METAL CHAIN GUARD WAS FITTED TO THIS SWING ARM INSTEAD OF THE PREVIOUS BLACK PLASTIC ITEM. THREE 6 MM CHROME BOLTS SECURED IT TO THE ARM.

NEW PART NUMBERS:SWING ARM: 33001-090CHAIN GUARD: 36014-069MOUNTING BOLTS: 110N0614

SEAT ASSEMBLY:MANY AFTER MARKET SEATS WERE AVAILABLE FOR THE 900 SERIES INCLUDING SUCH ITEMS AS "KING AND QUEEN" AND "BUDDY SEATS".KAWASAKI PRODUCED A STEPPED UP SEAT FOR THE LTD WHICH UTILISED THE ORIGINAL BASE AND FASTENINGS BUT STILL MANAGED TO GIVE A CUSTOM LOOK.IT WAS STILL COVERED WITH A BLACK VINYL COVER.NEW PART NUMBER:SEAT: 53001-130

REAR FENDER:THE REAR FENDER ON THE LTD WAS MODIFIED TO GIVE A CHOPPED DOWN LOOK. THE FENDER WAS STILL SHORT AND CHROME BUT WAS NOW MUCH NEATER.THE INNER PLASTIC FENDER WAS ALSO MODIFIED TO ACCEPT THE NEW SWING ARM AND CHAIN GUARD.NEW PART NUMBERS:INNER REAR FENDER: 35022-137REAR FENDER: 35022-151

REAR GRAB RAIL:DUE TO THE DIFFERENT SEAT FITTED, A NEW GRAB RAIL WAS REQUIRED.THIS WAS STILL CHROME BUT BECAUSE OF THE HEIGHT OF THE REAR OF THE SEAT A HIGHER GRAB RAIL WAS NEEDED.NEW PART NUMBER: 35032-040

REFLECTORS:AS WITH ALL AMERICAN MODELS, TWO SMALL CIRCULAR ORANGE REFLECTORS WERE FITTED TO THE FRAME TUBES JUST UNDERNEATH THE FRONT OF THE TANK.NEW PART NUMBERS:REFLECTOR: 28012-016

EXHAUST SYSTEM:THE LTD WAS FITTED WITH A FOUR INTO TWO EXHAUST SYSTEM INSTEAD OF THE USUAL FOUR INTO FOUR. THIS SYSTEM WAS MADE BY THE AMERICAN JARDINE COMPANY ESPECIALLY FOR KAWASAKI.

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UNLIKE THE GENUINE SYSTEM WHICH WAS DOUBLED SKINNED, THE JARDINE PIPES WERE SINGLE SKINNED AND TENDED TO TURN YELLOW AND BLUE AT THE FIRST HINT OF HEAT. HOWEVER THIS ALL ADDED TO THE CHARACTER OF THE LTD.THE MUFFLERS ENDED IN A BELL SHAPE AND WERE MOUNTED QUITE LOW. THIS DID NOT HELP IN THE GROUND CLEARANCE DEPARTMENT AND IT IS VERY DIFFICULT TO FIND A LTD WITHOUT SCRAPPED MUFFLERS.THEY MOUNTED IN THE SAME PLACE AS THE STANDARD PIPES BY TWO CHROME 10MM X 50MM BOLTS AND NUTS.THE JARDINE SYSTEM WAS QUITE A BIT LOUDER THAN THE STANDARD SYSTEM WHICH IMPRESSED OWNERS A LOT. JARDINE WENT ON TO SELL THIS SYSTEM AS AN AFTER MARKET PRODUCT ALL AROUND THE WORLD. NEW PART NUMBERS:MUFFLER: 18001-199 LHMUFFLER: 18001-200 RHDOWN PIPE: 18049-076 LH/RH OUTERDOWN PIPE: 18049-077 LH INNERDOWN PIPE: 18049-078 RH INNERMOUNTING BOLTS: 92007-050

BODY WORK: CLASSIC RED.

THE LTD WAS ONLY OFFERED IN ONE COLOUR. THIS WAS CALLED CLASSIC RED. TWO THIN PINSTRIPES, ONE GOLD AND ONE A BRIGHTER RED, RAN AROUND THE TAILPIECE, FUEL TANK AND FOR THE FIRST TIME AROUND THE SIDE PANELS.THE TAIL PIECE WAS THE SAME SHAPE AS THE Z900-A4 PART, AS WAS THE SIDE PANELS BUT THE TANK WAS A MUCH SMALLER PEANUT SHAPE AFFAIR.THE TANK CAP REMAINED THE SAME AS THE Z900-A4 BUT THE FUEL TAP WAS MODIFIED BECAUSE OF THE SLIMMER DESIGN OF THE TANK. THE OUTLET PIPES ON THE NEW TAP WERE ANGLED TO GIVE CLEARANCE FROM THE CARBS.THE SMALLER TANK BADGES THAT WERE FIRST USED ON THE ORIGINAL 1973 Z1 WERE USED ON THE LTD, KEEPING IN LINE WITH THE SMALLER TANK.INDEED THE LTD TANK HELD NEARLY 25% LESS FUEL THAN THE Z900-A4.THE SIDE PANEL EMBLEMS WERE CHANGED AND NOW READ "KZ900" WITH THE LEGEND "LTD" UNDERNEATH IT. THIS LEGEND WAS EMBOSSED IN RED.THE WHOLE PACKAGE WAS VERY STRIKING FOR IT'S TIME AND IT STILL LOOKS VERY FRESH NOW.NEW PART NUMBERS:FUEL TANK: 51001-114-8BFUEL TAP: 51023-058TANK BADGES: 56013-045TAIL PIECE: 53043-013-8BSIDE PANEL: 36001-054-8B LHSIDE PANEL: 36007-051-8B RHEMBLEM: 56018-260 LH KZ900 LTDEMBLEM: 56018-263 RH KZ900 LTD

OWNERS HANDBOOK: 99995-290-01

CHAPTER EIGHT:THE Z2-750.

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1973 Z2-750 RS

WHEN THE DESIGN TEAM IN JAPAN DECIDED TO PRODUCE THE 900 FOR THE REST OF THE WORLD THEY DID NOT FORGET ABOUT THEIR HOME MARKET.THE ORIGINAL DESIGN FOR THE 750 WAS DUSTED OFF AND IT WAS DECIDED THAT IF THE WORLD WAS TO GET THE BEST IN THE WORLD, THEN JAPAN WAS TO GET THE SECOND BEST BIKE IN THE WORLD, THE Z2. IN DECEMBER OF 1972 , KAWASAKI HELD A PRESS CONFERENCE AT THE TOKYO TAKANAWA PRINCE HOTEL AND PROUDLY PRESENTED THE Z2 TO JAPANESE DEALERS. PRODUCTION STARTED IN JANUARY OF 1973 AND THE FIRST DELIVERIES TO DEALERS WERE MADE IN MARCH. IT WAS AN INSTANT SUCCESS AND INITIALLY OUTSOLD THE CB750 BY 10%.

THE Z2 WAS IDENTICAL TO THE LARGER BIKE IN DESIGN EXCEPT FOR THE DISPLACEMENT OF JUST 746 CC AND SMALLER 26MM CARBS.IT WAS ONLY OFFERED IN THE BROWN AND ORANGE COLOUR OPTION FOR THAT YEAR.ENGINEER INAMURA DECIDED THAT SIMPLY REDUCING THE BORE SIZE OF THE Z1 WAS NOT GOOD ENOUGH. INSTEAD KAWASAKI CHANGED THE BORE AND THE STROKE TO 64MM X 58MM. THIS CHANGE REQUIRED A DIFFERENT CRANKSHAFT, CYLINDERS, PISTONS, PINS AND RINGS. THE REST OF THE MOTOR REMAINED THE SAME.

THE FINAL GEARING ON THE Z2 WAS CHANGED TO TAKE INTO CONSIDERATION THE DIFFERENT TORQUE CHARACTERISTICS OF THIS SMALLER MOTOR. THE FRONT ENGINE SPROCKET STAYED THE SAME AT 15 TEETH BUT THE REAR ONE WAS CHANGED TO A 42 TOOTHED ITEM. THIS REQUIRED THE USE OF A LONGER CHAIN AND SO A 96 LINK ITEM WAS FITTED. THIS GIVE A TOP SPEED OF AROUND 120 MPH WHICH WAS MORE THAN ACCEPTABLE FOR THE JAPANESE MARKET.AS NORMAL ON JAPANESE SPECIFICATION BIKES THE Z2 WAS FITTED WITH A SPEED WARNING DEVICE. THIS CONSISTED OF A RED WARNING LIGHT FITTED TO THE TOP OF THE HEADLAMP SHELL. THIS IS WHY THE Z1 HAS A RUBBER BUNG IN THERE.!THIS WARNING LIGHT WAS WIRED TO A SWITCH WHICH LIVED UNDERNEATH THE FUEL TANK WHICH IN TURN WAS WIRED TO ANOTHER SWITCH WHICH LIVED INSIDE THE SPEEDO ITSELF. THE FACE OF THE SPEEDO WAS CALIBRATED IN KPH MARKINGS WITH A RED LINE STARTING AT 80 KPH. WHEN THE NEEDLE REACHED 80 KPH, IT TRIGGERED THE SWITCH WHICH THEN LIT UP THE WARNING LIGHT. A BIT OVER THE TOP PERHAPS BUT THIS WAS THE LAW IN JAPAN. INTERESTINGLY, THE SERIES OF WIRES BETWEEN THE TWO SWITCHES RAN ALONG SIDE THE INSTRUMENT LIGHT LOOM BUT WAS NOT OFFERED AS A SEPARATE PART, NOR DID IT COME WITH THE INSTRUMENT LOOM.THE JAPANESE SPEC Z2 WAS FITTED WITH THE AMERICAN TYPE SHORT REAR FENDER BUT WITH THE EUROPEAN SPEC SEAT WITH A STRAP AND BUCKLES.ANOTHER STRANGE THING WAS THE USE OF ORANGE REFLECTORS ON THE REAR SHOCK ABSORBERS INSTEAD OF THE NORMAL RED.BLACK PLASTIC PLUG CAPS WERE USED, JUST LIKE THE AMERICAN Z1 ITEMS WHICH AGAIN WAS NORMAL FOR JAPAN.THE FRONT FOOTREST WERE THE NON FOLDING TYPE LIKE FITTED TO EUROPEAN BIKES.THE ONLY OTHER DIFFERENCE WAS OF COURSE THE SIDE PANEL BADGES. THESE NOW READ "750" WITH THE LEGEND "DOUBLE OVERHEAD CAMSHAFT" UNDERNEATH IT JUST LIKE THE Z1.ONLY A FEW DOZEN Z2 MODELS HAVE MADE IT TO THE UK, BUT INTEREST IN THIS RARE MODEL IS HIGH LEADING TO A SECTION OF THE CLASSIC KAWASAKI OWNERS CLUB BEING DEVOTED TO IT. THEY EVEN HAVE THEIR OWN RESIDENT Z2 EXPERT, JOHN BROOKES.

I AM LUCKY ENOUGH TO HAVE OWNED QUITE A FEW Z2`S OVER THE YEARS RANGING FROM 1973 BIKES UP TO A 1978 MODEL.I ONCE WROTE AN ARTICLE FOR A MAGAZINE DESCRIBING MY EXPERIENCE WITH THIS MODEL AND I LIKENED IT TO RIDING A Z1 WITH ONE OF THE PLUG CAPS MISSING.!! IT HAD ALL THE WEIGHT OF THE Z1 BUT ONLY 69 BHP.I RECEIVED LETTERS OF COMPLAINTS FROM OTHER Z2 OWNERS SAYING I WAS BEING UNFAIR. PERHAPS I WAS AND PERHAPS IF YOU HAD NEVER RODE A Z1 YOU MAY OF THOUGHT THE Z2 WAS OK, BUT HAVING RODE BOTH I HAVE TO STICK WITH MY ORIGINAL THOUGHTS.

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I RODE A Z2 TO A Z1 OWNERS CLUB RALLY IN NOTTINGHAM WITH A GOOD FRIEND OF MINE, IAN MANLEY ON A KAWASAKI 500 TRIPLE AND HE LEFT ME FOR DEAD!!. I HAD TO SCREW EVERY BIT OF PERFORMANCE OUT OF THE Z2 TO JUST KEEP UP WITH HIM. I ONLY CAUGHT UP TO HIM AT PETROL STATIONS. !!HOWEVER I DID WIN THE BEST BIKE AT THE RALLY SO THIS MORE THAN MADE UP FOR IT.

IN 1974 KAWASAKI PRODUCED THE Z2-A. THIS WAS STILL KNOWN IN JAPAN AS THE 750 RS. IT WAS OFFERED ONCE AGAIN ONLY IN ONE COLOUR OPTION, CANDY TONE YELLOW. THIS WAS THE SAME DESIGN AND COLOUR AS THE Z1-A OF COURSE.UNLIKE THE Z1-A, THE Z2-A RETAINED THE BLACK ENGINE FINISH INSTEAD OF THE NATURAL SILVER FINISH. THIS WAS DUE TO DEMAND FROM THE JAPANESE PUBLIC WHO PREFERRED THIS COLOUR.THE REFLECTORS ON THE REAR SHOCK ABSORBERS WERE NOW CHANGED TO THE MORE NORMAL RED ITEMS.ALL THE MODIFICATIONS THAT WERE IMPLEMENTED ON THE Z1-A WERE NOW MADE TO THE Z2-A AS WELL.

IN 1975 KAWASAKI PRODUCED THE 750 RS ONCE AGAIN IN ONLY ONE COLOUR OPTION, THAT OF THE Z1-B. HOWEVER, THEY CONTINUED TO CALL IT A Z2-A RATHER THAN A Z2-B. NOBODY SEEMS TO KNOW WHY THIS WAS.THE 1975 Z2 DID INHERIT ALL THE MODIFICATION THAT THE 900 HAD ENJOYED WHICH MAKES THIS EVEN STRANGER. PERHAPS THEY JUST LIKED THE SOUND OF IT. !!

IN 1976 THE Z2 BECAME THE Z750-A4 TO KEEP IT IN LINE WITH THE Z900-A4. ONCE AGAIN THE ENGINE WAS STILL FINISHED IN BLACK BUT NOW TWO COLOUR OPTIONS WERE OFFERED. THESE WERE THE TWO Z900-A4 COLOURS, GREEN AND BROWN.THE SIDE PANEL BADGES SIMPLY STATED Z750, BUT KAWASAKI ADDED A SMALL STICKER, ALMOST AS AN AFTER THOUGHT, UNDERNEATH THE MAIN EMBLEM WHICH SAID "FOUR". THIS WAS OBVIOUSLY TO STOP ANYBODY CONFUSING IT WITH THE Z750 TWIN WHICH HAD JUST BEEN RELEASED.THE SPEED WARNING LIGHT WAS REMOVED FROM THE HEADLAMP SHELL AND NOW FITTED TO A SMALL BRACKET WHICH BOLTED TO THE LEFT HAND HANDLEBAR MOUNT.

LATER IN 1976 SAW THE LAUNCH OF THE Z750-A5. THIS WAS IN REALITY THE 750 VERSION OF THE Z1000-A1. THE ENGINE FINISH YET AGAIN WAS IN BLACK.UNLIKE THE Z1000-A1 WHICH WAS NOW FITTED WITH A REAR DISK BRAKE, THE A5 CONTINUED WITH THE DEPENDABLE DRUM BRAKE.FOUR SEPARATE EXHAUSTS WERE STILL STANDARD ON THIS MODEL AS OPPOSED TO THE FOUR INTO TWO SYSTEM OF THE Z1000.THE TWO COLOUR OPTIONS OF THE Z1000-A1 WERE OFFERED, DIAMOND WINE RED OR DIAMOND SKY BLUE.

IN 1977 KAWASAKI MADE AVAILABLE TWO VERSIONS OF THE 750. THIS WAS THE Z750-D1 AND THE Z750-D1 EXPORT. THE JAPANESE MODEL WAS MUCH THE SAME BEING A SMALLER VERSION OF THE Z1000-A2 EXCEPT ONCE AGAIN, FITTED WITH A BLACK ENGINE AND THE FOUR INTO FOUR EXHAUST. HOWEVER, THE D1 WAS NOW FITTED, AT LAST, WITH THE REAR DISK BRAKE OF THE Z1000. TWO COLOUR OPTIONS WERE OFFERED, LUMINOUS RED OR LUMINOUS GREEN.THE EXPORT MODEL WAS MORE OR LESS THE SAME BUT THE ENGINE WAS NOW FINISHED IN THE NATURAL SILVER COLOUR. MOST OF THESE MODELS FOUND THERE WAY TO SOUTH AFRICA. I HAVE ONLY EVER SEEN GREEN BIKES FROM THIS COUNTRY ALTHOUGH OFFICIALLY BOTH COLOUR OPTIONS WERE OFFERED.THE SPEED WARNING SYSTEM WAS OBVIOUSLY NOT REQUIRED FOR THIS MARKET, SO THE VARIOUS SWITCHES AND LIGHTS WERE OMITTED.

THE Z2 RS FOUR DID CONTINUE IN JAPAN IN VARIOUS FORMS INCLUDING A 750 VERSION OF THE Z1000 MK11 AND EVEN A FUEL INJECTED MODEL.HOWEVER THE RANGE WAS DISCONTINUED IN 1980 WHEN KAWASAKI INTRODUCED THE Z750-E RANGE WHICH ITSELF WAS AN OVER BORED Z650 ENGINE.

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DESPITE THE RECENT RELAXATION OF THE "OVER 750" LAW IN JAPAN, THE NATIVES STILL HOLD CLOSE TO THEIR HEARTS THE LEGEND OF THE Z2 AND MANY MODELS ARE STILL OUT THERE FLYING THE FLAG FOR KAWASAKI.

I HAVE LISTED BELOW THE MAIN PARTS THAT WERE DIFFERENT FROM THE 1973-1975 Z1 RANGE OF MODELS:

CYLINDER BARRELS: 11006-014 (BLACK)PISTONS: 13001-063 STDPISTONS: 13027-061 1.00MM OVERSIZEPISTONS: 13029-065 0.5MM OVERSIZERING SET: 13008-048 STDRING SET: 13024-051 1.00MM OVERSIZERING SET: 13025-050 0.5MM OVERSIZEPISTON PIN: 13002-026CRANKSHAFT ASSY: 13031-044 CARBURETTOR ASSY: 16001-202 26MM MIKUNIREAR SPROCKET: 42041-132 42 TEETHDRIVE CHAIN: 92057-025 96 LINKSREAR SHOCK ABSORBER: 45014-089 (1973 MODEL WITH ORANGE REFLECTORS)REAR SHOCK ABSORBER: 45014-083 (1974/75 MODELS WITH RED REFLECTORS)EMBLEM: 56018-153 LH PANELEMBLEM: 56018-154 RH PANELSPEEDOMETER: 25001-073 KPHSPEED WARNING LIGHT: 23016-014SWITCH (SPEED): 25025-003SWITCH BRACKET: 32060-012

PARTS BOOK: 99997-103-04

CHAPTER NINE:OWNING AND RIDING THE Z1.

THE ROAD TESTS OF THE Z1 IN 1973 WERE IN GENERAL ALL VERY MUCH THE SAME. TESTERS MARVELLED AT THE SHEER SIZE AND POWER OF THIS ORIENTAL MASTER PIECE. THEY EVEN PRAISED THE HANDLING. !!THE FIRST MAN IN THE UK TO TEST ONE WAS BRIAN CHRICTON FOR MOTORCYCLE NEWS AND HE WAS AMAZED AT THE PERFORMANCE. IT WAS ONLY WHEN THE BIKE HE WAS RIDING BROKE INTO THE FAMOUS "SPEED WOBBLE" THAT THE TRUE REALITY OF THE RESPECT THIS MUSCLE BIKE DEMANDED CAME INTO FOCUS. LOOKING BACK NOW, THE WRITING WAS ALREADY ON THE WALL FOR THE FRAME DESIGNERS. PERHAPS KAWASAKI SHOULD HAVE SPENT MORE YENS ON THE FRAME RATHER THAN USING MOST OF THEIR BUDGET ON THE MOTOR.BUT WHAT A MOTOR. IF THE WORLD HAD CONTINUED THE ROMAN TRADITION OF STRAIGHT ROADS, THAN THE Z1 WOULD HAVE BEEN THE PERFECT BIKE. MOST RIDERS WOULD HAVE WILLINGLY GIVE UP CORNERS JUST TO SAMPLE THE Z1`S STRAIGHT LINE RUSH OF POWER. IN FACT MOST AMERICANS DID. !!THE Z1 BECAME THE ULTIMATE "TRAFFIC LIGHT" DRAG STAR IN THE USA. IN TRUTH IT WAS NOT MUCH QUICKER THAN THE PREVIOUS HOLDER OF THE CROWN, KAWASAKI'S OWN 750 H2 TRIPLE.BUT THIS NEW BIKE DID IT WITHOUT A BLUE HAZE SMOKE SHIELD AND WITH A CERTAIN DEGREE OF QUIETNESS AND RESPECTABILITY. THE NEW BUZZ WORD WAS "DOUBLE OVERHEAD CAM" EVEN THOUGH THIS IN ITSELF WAS NOTHING NEW. EXOTIC EUROPEAN RACE BIKES HAD ALREADY USED THIS CONFIGURATION AND EVEN HONDA HAD USED IT ON THE 450 TWIN BUT IT HAD NEVER BEEN USED IN CONJUNCTION WITH FOUR CYLINDERS AND A 903CC CAPACITY.

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IT WAS LIKE A BREATH OF FRESH AIR THE WHOLE WORLD OVER AND IT WAS MANY YEARS BEFORE THE REST OF THE JAPANESE COMPANIES CAUGHT UP. KAWASAKI WERE NUMBER ONE AND NOT FOR THE FIRST TIME OR LAST TIME.

IT IS HARD TO BELIEVE NOW THAT THE Z1 WAS CONSIDERED TO BE A BIG BIKE. THROWING A LEG OVER ONE NOW IS NOWHERE NEAR AS DAUNTING AS IT WAS 25 YEARS AGO. IN FACT IT FEELS QUITE SMALL IN COMPARISON WITH MODERN SPORTS OR CRUISER BIKES.THE FIRST IMPRESSION YOU GET IS THAT OF COMPACTNESS. EVERYTHING FALLS NEATLY TO HAND, A CLICHÉ IN FACT WHICH BECAME A SEVENTIES TRADE MARK. YOU SIT ON A Z1 AS OPPOSED TO SITTING IN IT. THE WIDE HIGH HANDLEBARS SPREAD YOUR ARMS APART AND BY THE TIME YOUR FEET ARE ON THE SENSIBLY PLACED FOOTREST, YOU FEEL AS THOUGH YOUR IN A COMFORTABLE ARMCHAIR.THAT IS UNTIL YOU REACH ANY SORT OF SPEED OF COURSE, THEN YOUR SAT IN A WIND TUNNEL.! THE UPRIGHT POSITION IS GREAT UP TO ABOUT 40 MPH, YOU FEEL LIKE YOUR ON TOP OF THE WORLD. TRULY KING OF THE ROAD.THE CLUTCH IS NORMALLY LIGHT IN OPERATION BUT THE RELEASE MECHANISM ,TO WHICH THE CABLE ATTACHES, IS DOWN NEXT TO THE FRONT SPROCKET AND IT CAN GET COVERED IN DIRTY CHAIN LUBRICANT WHICH SOON RESULTS IN A STIFFER OPERATION. PERIODIC CLEANING OF THIS PART IS REQUIRED.THE THROTTLE IS NORMALLY QUITE LIGHT BUT POOR ROUTING OF THE CABLES CAN CAUSE IT TO STICK. THE CARBS THEMSELVES HAVE A LARGE RETURN SPRING BUT THIS CAN CLOG UP WITH DIRT CAUSING A STICKY THROTTLE. THE LINKAGES ON THE EARLY CARBS DO WEAR WITH AGE AND OBTAINING A RELIABLE TICK OVER CAN SOMETIMES PROVE VERY DIFFICULT. THE FIRST THING A NEW OWNER SHOULD DO IS TO GET A TRAINED MECHANIC TO CHECK, CLEAN AND BALANCE THE CARBS. THE DIFFERENCE CAN TURN A BIKE RUNNING LIKE A "DOG" INTO A MUCH MORE PLEASANT RIDE. THE CARBURATION IS VERY SUSCEPTIBLE TO THE EXHAUST AND AIR FILTRATION SYSTEM THAT IS FITTED. NON STANDARD PARTS ARE ALWAYS HARD TO SET UP. YOU HAVE BEEN WARNED.!!!THE SWITCHGEAR WAS TYPICAL JAPANESE AND VERY RELIABLE IN OPERATION. THE ONLY PROBLEM STEMS WITH THE WIRES HARDENING OVER TIME AND BRAKING UP, USUALLY AROUND THE HEADSTOCK AREA. THE SPRING BEHIND THE STARTER BUTTON CAN SOMETIMES WEAKEN CAUSING NO CONTACT. A REPLACEMENT BUTTON IS AVAILABLE UNDER PART NUMBER: 27010-1009 OR YOU CAN, OF COURSE, DUST OFF THE KICK-STARTER. !ACCELERATION OF THE Z1 WAS AMAZING, NOWADAYS IT CAN ONLY BE COMPARED WITH A GOOD 400 BUT WITH ONLY A HANDFUL OF COMPETITORS IN 1973, INCLUDING THE CB750 AND A FEW TWINS, IT WAS MORE THAN ENOUGH.UNLIKE PREVIOUS MODELS FROM KAWASAKI, THE H1 AND H2 TRIPLES, THE POWER OF THE Z1 STARTED AT TICK OVER AND CONTINUED ALL THE WAY UP TO THE 9000 RPM RED LINE. AT ANY SPEED IN ANY GEAR ON ANY DAY YOU COULD BLAST PAST THAT FOUR WHEELED VECHILE IN FRONT OF YOU IN TOTAL CONFIDENCE. THE ONLY THING TO AVOID WAS A FEW EXOTIC EUROPEAN SPORTS CARS BUT EVERYTHING ELSE WAS FAIR GAME. THE AVERAGE HORSEPOWER OF A TYPICAL 1200CC CAR WAS 77 BHP AT THAT TIME SO THE 82 BHP OF THE Z1 WAS MORE THAN ENOUGH TO PUT YOU IN FRONT. NON MOTORCYCLIST OF THE TIME TOOK TO THE Z1 AS A FASHION STATEMENT. POP STARS WHO HAD NEVER RIDDEN ANYTHING BIGGER THAN A RALEIGH WISP WERE SUDDENLY RAVING ABOUT THE Z1. THE Z1 WAS "COOL" AND "GROOVY" AND "HIP".IT WAS EVERYTHING THE CB750 SHOULD HAVE BEEN. HONDA WERE TOO BUSY TELLING EVERYONE THAT "YOU MEET THE NICEST PEOPLE ON A HONDA" WHILE KAWASAKI WERE TELLING EVERYONE "LET THE GOOD TIMES ROLL". THE CB750 WAS THE OSMONDS OF THE BIKE WORLD WHILE THE Z1 WAS THE ROLLING STONES, BRASH, RUDE, UP FRONT AND IN YOUR FACE. HOWEVER, THIS DID NOT STOP BRITISH COMEDIAN DICK EMERY FROM BUYING ONE, ALTHOUGH THIS DID NOT STOP ROCK STAR GREG LAKE FROM OWNING ONE TOO.!!!!THE HANDLING OF THE Z1 CAN ONLY BE DESCRIBED AS COMPROMISED. ALL THAT POWER ON HAND HAD TO BREAK OUT SOME WHERE. THAT SOME WHERE WAS USUALLY HALF WAY THROUGH A BEND ON A WET DAY. A WELL KNOWN WRITER OF A MAGAZINE OF THE TIME FOLLOWED A Z1 TEST RIDER AROUND A TRACK WITH A CAMERA AND SHOWED PHOTOGRAPHS OF THE Z1 BRAKING INTO A WOBBLE JUST AFTER THE POWER WAS EITHER TURNED ON OR TURNED OFF. THIS THEY CONCLUDED WAS THE FAULT OF THE SWINGING ARM. SALES OF DRESDA SWING ARMS INCREASED ACCORDINGLY !!. THE WOBBLES, HOWEVER, CONTINUED.THE PROBLEM WAS IN TRUTH MUCH DEEPER THAN THIS. THE TEST OF TIME WOULD PROVE THAT THE MAIN PROBLEM WAS WITH THE FRAME DESIGN OR RATHER WITH THE LACK OF

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EXPERIENCE OF THE FRAME DESIGNERS. THE TROUBLE WITH THE JAPANESE AT THAT TIME WAS THAT A SEPARATE TEAM WOULD DESIGN THE ENGINE AND ANOTHER ONE WOULD DESIGN THE FRAME AND RUNNING GEAR. IN FACT, THE WHEELS AND BRAKES ON THE Z1 WERE FIRST USED IN 1972 ON THE H2 MACH IV 750.A PRODUCTION AND COSTING COMPROMISE.

IT WAS NOT UNTIL 10 YEARS LATER, WHEN THE GPZ900R WAS LAUNCHED, THAT THE FRAMES COULD EVER MATCH THE ENGINES THAT KAWASAKI PUT INTO THEM.THIS ALL ADDED TO THE Z1 LEGEND OF COURSE. WAS YOU MAN ENOUGH TO TAKE ON THE Z1 ?. MANY PEOPLE CRASHED TRYING, ME INCLUDED.!!!THERE WAS A LOT OF HYPE IN THOSE DAYS, REMEMBER WHEN THE H2 COULD WHEELIE IN EVERY GEAR, DOWN HILL AND EVERYBODY OVER 30 HAD ONCE OWNED A VINCENT BLACK SHADOW THAT COULD DO 140 MPH AND WOULD STILL BE AROUND WHEN YOUR "JAP CRAP" WAS RECYCLED INTO A HAIR DRYER. THERE WAS NOT MUCH GOING ON IN THE TRADES DESCRIPTION DEPARTMENT AT THAT TIME.! IN FACT, ALCOHOL AND TOBACCO WERE STILL ALMOST BEING SOLD AS HEALTHY PRODUCTS. THE ONLY GOVERNMENT HEALTH WARNINGS WAS ON BERNARD MANNING AND JUDGE DREAD, OH, AND LITTLE JIMMY OSMOND. !

WILD CLAIMS WERE NORMAL FROM ALL THE MANUFACTURES, INCLUDING KAWASAKI. THEY CLAIMED THAT THERE FRONT BRAKE ON THE Z1 WAS "RETRO ROCKET" IN OPERATION. REMEMBER THE "BULL WORKER", YOU KNOW THAT SPRING LOADED FITNESS DEVICE THAT TURNED YOU INTO CHARLES ATLAS OVERNIGHT. WELL YOU NEEDED THAT TO STOP THE Z1 QUICKLY. THE AMOUNT OF PRESSURE REQUIRED TO PULL THAT LEVER IN WAS TREMENDOUS. EVENTUALLY THE BIKE WOULD STOP, IF IT WAS RAINING THEN YOUR BEST BET WAS BIKE CLIPS, WOODEN CLOGS AND A BIBLE. !WELL KNOWN TELEVISION PRESENTER STEVE BERRY ONCE SAID THAT STOPPING A Z1 WAS LIKE STOPPING AN ELEPHANT WITH TWO ROLLED UP NEWSPAPERS.!!!THE BACK BRAKE IN CONTRAST WAS SUPERB. PURISTS WILL REMEMBER THAT BEFORE COMBINED BRAKING SYSTEMS, WE HAD TO USE THE FRONT BRAKE AND THEN THE REAR BRAKE JUST TO STEADY US. WHAT A LOAD OF TWADDLE !. Z1 OWNERS COULD BE EASILY RECOGNISED BY THERE DIRT TRACK STYLE STOPPING METHODS, THEIR RIGHT LEG JUMPING UP AND DOWN ON THE PEDAL.THE OTHER BRAKING PROBLEM WAS WITH THE EXCESSIVE SQUEALING THAT YOU GOT FROM THE PADS. THIS WAS EAR PIECING. THE ONLY GOOD NEWS WAS THAT PEDESTRIANS COULD HEAR YOU COMING FROM 100 YARDS UP THE ROAD. KAWASAKI HAD INVENTED A MOTORCYCLE EARLY WARNING SYSTEM WITHOUT REALISING IT !.IN FAIRNESS KAWASAKI DID PRODUCE A SHIM WHICH FITTED BEHIND THE PADS TO REDUCE THIS NOISE AND IN REALITY THE FRONT BRAKE OF THE OTHER BIKES AVAILABLE WERE NOT MUCH BETTER. THE SAME SET UP WORKED QUITE WELL ON THE LIGHTER 750 TRIPLE SO PERHAPS THE DOUBLE DISK SET UP OFFERED BY KAWASAKI WAS MORE OF AN NECESSITY THAN AN OPTION ON THE Z1.

THE ROAD HOLDING OF THE Z1 WAS ACCEPTABLE IN THE DRY BUT IT WAS ANOTHER STORY WHEN THE ROADS WERE WET. THE JAPANESE DUNLOP TYRES WERE CONSIDERED TO BE ONE OF THE WORST IN THE WORLD. "JAPLOPS" AS THEY WERE KNOWN WERE FITTED TO MANY JAP BIKES AT THAT TIME AND THE Z1 WAS NOT THE ONLY BIKE TO SUFFER. MANY OWNERS REPLACED THEM WITH "TT100" ITEMS THAT WERE AT BEST UNSUITABLE AND AT WORST UNSAFE. THEY GIVE THE Z1 A RAZOR EDGE FEELING THAT SOME OWNERS CONFUSED WITH A "GOOD HANDLING FEELING".THE "TT100" WAS A GOOD TYRE WHEN FITTED TO THE BIKES IT WAS MEANT FOR BUT IT DID NO JUSTICE TO THE Z1. THE Z1 NEEDED AND STILL NEEDS A RIBBED FRONT TYRE TO GIVE IT DIRECTIONAL STABILITY. TYRE CHOICE IN THE EARLY SEVENTIES WAS LIMITED SO OWNERS JUST HAD TO PUT UP WITH BAD HANDLING. NOT UNTIL METZELERS, RED ARROWS AND CONTINENTALS WERE RECOMMENDED DID THINGS GET BETTER.EVERY ROAD TEST OF THE TIME SLATED THE TYRES. NOT WITHOUT REASON. TROUBLE WAS WHEN FITTED WITH DIFFERENT TYRES THINGS NORMALLY GOT WORSE. THE ONLY ANSWER WAS RACE CUT SLICKS WHICH WERE OF COURSE VERY EXPENSIVE AND NOT FOR ROAD USE.THE Z1 STEERED OK FOR A SEVENTIES BIKE, IT WAS HELPED TREMENDOUSLY OF COURSE BY THE WIDE HIGH HANDLEBARS WHICH GIVE PLENTY OF LEVERAGE AND MADE FOR EASY PUSHING AROUND WHEN MANOEUVRING THE BIKE INTO THE GARAGE.

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THE FOLKLORE OF THE Z1 LEGENDARY HANDLING QUIRKS WAS AT TIMES WELL EXAGGERATED AND MANY FALSE CLAIMS WERE MADE BY MOTORCYCLISTS WHO HAD NEVER EVEN SAT ON A Z1, LET ALONE RIDDEN ONE.BEWARE OF BORN AGAIN BIKERS TELLING STORIES HOW THEY LAPPED THE ISLE OF MANN WITHIN SECONDS OF THE LAP RECORD ON A Z1. IN THOSE DAYS BEER WAS PURCHASED IN "PARTY SEVEN" CANS AND CONSUMED IN GREAT QUANTITIES. ASK HOW MANY THEY HAD DRUNK BEFORE THE SUPPOSED RIDE OF THEIR LIVES. THE Z1 WAS GEARED TO PULL 140 MPH AT THE RED LINE IN TOP GEAR, BUT IT IS AMAZING HOW MANY PEOPLE CLAIMED NEARER 160 MPH.!! THE MORE THEY DRUNK THE FASTER AND BETTER HANDLING THE Z1 GOT !.

THE Z1 WAS FAST. THERE IS NO DOUBT ABOUT THAT. IN 1973 ONLY THE RICH AND FAMOUS COULD NORMALLY ACHIEVE OVER 125 MPH. NOW FOR A SMALL FORTUNE OF AROUND £1100 YOU BE IN CHARGE OF A ROCKET SHIP. JUST HOW MUCH OF A FORTUNE IS THAT YOU MAY ASK ?. WELL YOU COULD HAVE HAD A MARS BAR FOR ABOUT 2 AND A HALF NEW PENCE THEN. SO YOUR £1100 COULD HAVE GOT YOU ABOUT 44,000 MARS BARS AND PROBABLY A BAD CASE OF ACNE. COMPARE THAT TO THESE DAYS, SAY AGAINST A ZZR1100. YOU WOULD ONLY HAVE TO SWAP ABOUT 20,000. SO YES IT WAS A SMALL FORTUNE. BUT IN THOSE DAYS THE AVERAGE MOTORCYCLIST SPENT ALL HIS TIME AND MONEY ON HIS CHOSEN MOUNT UNLIKE TODAY WHERE THE BIKE IS USUALLY A WEEKEND TOY SHARING THE GARAGE WITH ANOTHER BIKE AND A CAR OR TWO. BORN AGAIN BIKERS COULD ONLY DREAM ABOUT OWNING A Z1 IN THE SEVENTIES, WHILE NOW THEY BUY THEM FROM THE "DISPOSABLE CASH" FUND. THE TRUE TOP SPEED OF THE Z1 WAS WHAT COULD BE ACHIEVED IN FOURTH GEAR BECAUSE FIFTH WAS MORE OF AN OVERDRIVE GEAR. FOURTH AT THE RED LINE WOULD SHOW YOU 125 MPH ON THE SPEEDO, AND CHANGING INTO FIFTH MAY HAVE GOT YOU ANOTHER 5 MPH IF THE ROAD WAS LEVEL. THE FASTEST I HAVE PERSONALLY SEEN ON THE SPEEDO OF A Z1 IS 135 MPH, DOWN HILL WITH THE WIND BEHIND ME. THE ONLY FASTER Z1 I HAVE HAD IS MY Z1-R TURBO, WHICH HAS SHOWN ME 160 MPH. IT HAS ONLY DONE THIS ONCE, IT PROBABLY WOULD AGAIN BUT I WOULD CERTAINLY NOT.!!160 MPH ON MY ZZR1100 IS A BREEZE, ON THE Z1-R IT WAS SCARY. VERY, VERY SCARY.! NEEDLESS TO SAY, AT LEAST THREE ROLLED UP NEWSPAPERS WERE REQUIRES TO STOP IT.!!!THE TORQUE CHARACTERISTICS OF THE Z1 MOTOR WAS VERY IMPRESSIVE. YOU COULD TRICKLE ALONG IN TRAFFIC AT 25 MPH IN TOP GEAR AND THEN WITHOUT CHANGING DOWN, ACCELERATE UP TO 125 MPH WITHOUT AS MUCH AS A HICCUP FROM THE MOTOR. THE BIG TWINS FROM BMW AND MOTOGUZZI COULD NOT DO THIS OR INDEED THE MIGHTY HARLEY DAVIDSON`S. NO, THE Z1 WAS IN A WORLD OF IT'S OWN.EVEN THE CB750 WAS OVERSHADOWED, BUT THE HONDA WAS ATTRACTING A DIFFERENT TYPE OF RIDER. EVEN THEN, LOYALTY WAS VERY STRONG AND ONCE A KAWASAKI OWNER THEN ALWAYS A KAWASAKI OWNER. THIS IS STILL TRUE TODAY, KAWASAKI HAVE THE BIGGEST BRAND LOYALTY OF ALL THE BIG FOUR JAPANESE MANUFACTURERS. I ONCE RODE A Z1 ALL THE WAY FROM MANCHESTER TO THE SOUTH OF FRANCE, ONLY STOPPING FOR THE FERRY AND THE CALL OF NATURE. IT CARRIED TWO OF US AND ALL OUR LUGGAGE WITHOUT A SINGLE PROBLEM. IN TOTAL IT USED 1 LITRE OF OIL AND AVERAGED 40 MILES TO THE GALLON. THE CHAIN ONLY NEEDED ADJUSTING TWICE IN A THOUSAND MILES. MANY YEARS LATER I STRUGGLED TO DO THE SAME JOURNEY ON A GPZ900R, THE Z1 WAS THAT GOOD. (OR WAS I JUST GETTING OLDER !!)

ROAD TESTERS AT THE TIME SHOWED CONCERN ABOUT THE LIFE EXPECTANCY OF THE CHAIN AND TYRES IN NORMAL ROAD USE. KAWASAKI HAD USED THE BIGGEST CHAIN POSSIBLE ON THE Z1, A 630 UNIT, BUT THEY KNEW FROM THERE OWN TESTS THAT THE Z1 COULD EAT A CHAIN WITHIN 3000 MILES. THE CHAIN OILER FITTED TO THE Z1 WAS HELPING BUT STILL IT WAS A MAJOR CONCERN. MANY LONG TERM TESTS ON THE Z1 CONCLUDED THAT THE CHAIN WAS NOT UP TO THE JOB, EVEN WITH THE CHAIN OILER ADJUSTED TO FULL OUTPUT. HOWEVER IN THE ABSENCE OF ANY REASONABLE ALTERNATIVE, KAWASAKI HAD NO OPTION BUT TO COVER THE FIRST REPLACEMENT UNDER WARRANTY. NORMALLY WEAR AND TEAR ITEMS WERE NOT INCLUDED. THIS GOODWILL GESTURE COUPLED WITH THE STANDARD 6 MONTHS WARRANTY ATTRACTED NEW AND REPEAT CUSTOMERS.THE TYRES WERE ANOTHER STORY. OWNERS COULD NOT WAIT TO WEAR THEM OUT, USUALLY AFTER ONLY 5000 MILES. KAWASAKI HAD NO WARRANTY CLAIMS TO WORRY ABOUT THERE.!!

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KAWASAKI PREVIOUSLY HAD ONLY OFFERED 3 MONTHS WARRANTY ON THE TWO STROKE MODELS, SO THE 6 MONTHS COVER ON THE Z1 WAS A STATEMENT OF CONFIDENCE IN THE PRODUCT. IT WOULD BE MANY YEARS BEFORE THEY OFFERED A LONGER WARRANTY AND NOT UNTIL HONDA DID.THE SIGHT OF A Z1 ON THE ROAD, IN THE UK, IN 1973 WAS QUITE RARE. ONLY AN HANDFUL OF BIKES WERE REGISTERED, SO THE Z1 OWNERSHIP CLUB WAS A TAD SLIM. AN OWNER WOULD HAVE TO PUT UP WITH A CROWD OF ADMIRERS WHERE EVER HE PARKED UP AND BE WILLING TO DISCUSS AND ANSWER ALL SORTS OF QUESTIONS. THE MOST POPULAR OF COURSE BEING, "HOW FAST IS IT ?". THIS WAS USUALLY FOLLOWED BY "HOW MUCH WAS IT ?". THIS WAS DEFINITELY NOT A BIKE FOR THE SHRINKING VIOLET.!!RIDING A Z1 IN THE NINETIES IS OF COURSE, NOT MUCH DIFFERENT. YOU STILL HAVE A CROWD OF ADMIRERS WHERE EVER YOU PARK. THE QUESTIONS YOU GET ASKED HOWEVER, HAVE CHANGED. THOUSANDS OF ROAD TESTS MUST HAVE BEEN MADE OF THE Z1 DURING THE FIRST FEW YEARS AND NOT ONE OF THEM TO MY KNOWLEDGE EVER SAID IT WAS BAD. THE MOTORCYCLING PRESS AND PUBLIC WERE JUST HAPPY TO HAVE IT. THE MAGNIFICENCE OF THE BIKE MORE THAN MADE UP FOR ANY SHORTCOMINGS.

THE Z900-A4 IN 1976 WAS ACKNOWLEDGED BY EVERYONE AS A POOR ADVANCEMENT OF THE Z1 RANGE. THIS WAS BASED ON THE LOWER POWER OUTPUT OF THE MOTOR DUE TO THE SMALLER 26MM CARBS. IN AN AGE WHEN BIGGER WAS BEST, KAWASAKI WERE VERY BRAVE TO MAKE THIS CHANGE. THE RESULTS OF THE SMALLER CARBS WAS A MUCH BETTER BIKE TO RIDE BUT TESTERS COMPLAINED THAT THE TOP END RUSH OF THE Z1 WAS GONE. WHAT THEY FAILED TO REALISE OR MORE TO THE POINT, FAILED TO APPRECIATE WAS THE IMPROVEMENT IN MID RANGE WHERE IT REALLY MATTERED. THE VAST IMPROVEMENT IN THE CARBURATION IN GENERAL WAS ALSO LOST ON THESE POWER CRAZED TESTERS. THE NEED FOR SPEED WAS FIRMLY SET IN THE TYPICAL ROAD TESTERS AGENDA. THIS SADLY WOULD BE THE CASE FOR MANY YEARS TO COME. I PERSONALLY THINK THE Z900-A4 WAS THE BEST OF ALL THE 900`S. THE HANDLING OF THE Z900 WAS MUCH IMPROVED ALTHOUGH IT STILL NEEDED TREATING WITH RESPECT. THE STIFFER FRAME HELPED BUT IT WAS STILL LET DOWN BY AN INFERIOR SWING ARM AND DIABOLICAL REAR SHOCKS. THE FRONT END OR RATHER THE TWIN FRONT BRAKES TRANSFORMED THE Z900 INTO A MUCH SAFER MOTORCYCLE.BRAKING, AT LEAST IN THE DRY, WAS NOW A TWO FINGER ON THE LEVER AFFAIR. YOU COULD IF YOU WISHED, SQUEAL THE FRONT TYRE TO A SAFE PREDICTABLE STOP. IN THE WET HOWEVER, IT WAS BACK TO THE PRAYER BOOK.!!!THE THREE FUSE SYSTEM MEANT NO MORE PUSHING THE BIKE HOME WHEN THE MAIN FUSE BLEW. THE BACK UP SPARE FUSES WERE NORMALLY ENOUGH TO GET YOU HOME SO YOU COULD SORT THE PROBLEM OUT.THE MODIFIED IDIOT LIGHTS WERE EASIER TO SEE AND THE HAZARD LIGHT WERE, WELL USELESS !!!!. WHO NEEDS HAZARD LIGHTS ON A MOTORCYCLE ?. THE INDICATOR BUZZER WAS AS WE HAD SAID EARLIER, A VERY ANNOYING, EMBARRASSING PIECE OF KIT. THE LEAST SAID THE BETTER.!!THE MODIFIED PLASTIC TOOLBOX WAS A GOOD IDEA BUT THE WEIGHT OF THE TOOL KIT MEANT THAT THE TRAY BROKE ALMOST INSTANTLY. PERHAPS NOT SUCH A GOOD IDEA AFTER ALL !.THE NEW LOCKING FUEL CAP AND SEAT LOCK WERE MUCH BETTER AND THE MODIFIED AIR FILTER SYSTEM MADE EVERYTHING A LOT QUIETER. NO LONGER DID IT SOUND AS IF YOU LEG WAS BEING SUCKED INTO THE AIR BOX. NOT EVERYBODY AGREED WITH ME HERE AND MANY OWNERS REMOVED THE AIR BOX SILENCER TO REGAIN THAT FAMILIAR SLURPING SOUND WHEN YOU OPENED THE THROTTLE.THE MODIFIED QUIETER EXHAUST WERE NOT THAT MUCH DIFFERENT TO THE EARLIER ITEMS BUT THIS WAS A DEFINITE SIGN OF WHAT WAS YET TO COME. TYPE APPROVAL, NOISE EMISSION CONTROL AND THE NEED TO CONFORM TO INCREASING REGULATIONS.ALL IN ALL THE Z900 WAS A MUCH BETTER BIKE THAN THE Z1, BUT AT THE END OF THE DAY, THAT EXTRA ONE BRAKE HORSE POWER OF THE Z1 MADE ALL THE DIFFERENCE TO THE DISCERNING MOTORCYCLIST. THE Z900-A4 HOWEVER WAS STILL THE KING OF THE ROAD AND IN MY OPINION THE GREEN Z900-A4 IS THE BEST LOOKING BIKE THAT THE JAPANESE HAVE EVER PRODUCED.

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THE AMERICAN KZ900-A4 IS VERY POPULAR ON BRITISH ROADS THESE DAYS AND DESPITE ONLY HAVING ONE DISK, IT IS STILL MUCH BETTER BRAKED THAN THE Z1. THE DESIGN OF THE LATER CALLIPER AND DISK WAS OBVIOUSLY A MUCH BETTER ONE.BY 1976 THE COMPETITION WAS HOTTING UP AND MORE BIG BORE MACHINES WERE NOW AVAILABLE. HONDA HAD RELEASED THE GL1000 GOLDWING THE PREVIOUS YEAR HAS THERE FLAGSHIP AND THIS TOOK MANY SALES AWAY FROM KAWASAKI. THE WING PRODUCED 3 BHP MORE THAN THE Z900 AND HAD WATER COOLING AND SHAFT DRIVE. ALTHOUGH HEAVIER AND SLOWER THAN THE Z900 IT HAD THE MIGHT OF HONDA AND ITS CONSIDERABLE DEALER NETWORK BEHIND IT. THE HANDLING OF THE BIG HONDA WAS SAFE AND PREDICTABLE, SUDDENLY THE WRITING WAS ON THE WALL FOR THE Z900. THIS NEW KID ON THE BLOCK WAS ALSO SELLING WELL IN THE STATES, KAWASAKI HAD NO OPTION BUT TO SIT UP AND TAKE NOTICE.THE FOLLOWING YEAR KAWASAKI REPLACED THE Z900 WITH THE 1015CC Z1000-A1. THIS WAS OVER 15CC BIGGER THAN THE WING AND THUS ENDED THE REIGN OF THE Z1-900 RANGE. THE KING IS DEAD, LONG LIVE THE KING !.

THE ACTUAL OWNERSHIP OF A Z1 WAS PRETTY PAINLESS BUT LIKE ANY OTHER MOTORCYCLE, THINGS DID GO WRONG ON OCCASIONS.THE ROAD TESTS OF THE Z1 AS REPORTED IN THOSE EARLY YEARS RARELY LASTED MORE THAN A DAY OR SO, SO LONG TERM OWNERSHIP PROBLEMS WAS LEFT TO THOSE WHO HAD BOUGHT ONE TO DISCOVER THEMSELVES. PERHAPS THE BIGGEST PROBLEM WITH THE FIRST MODELS WAS THE EXCESSIVE OIL LEAKS FROM THE CYLINDER HEAD TO BARREL JOINT. MOST OF THE PROBLEM BIKES WERE SENT TO AMERICA SO ONLY A FEW UK BIKES WERE EFFECTED. NEVER THE LESS IN MAY 1973 KAWASAKI MODIFIED THE HEAD GASKET TO A ONE PIECE AFFAIR WITH AN O`RING AROUND THE CAM CHAIN TUNNEL. THIS SEEMED TO CURE THIS PROBLEM.AS WE HAVE MENTIONED BEFORE, THE CHARGING SYSTEM ON THE Z1 WAS SOMEWHAT FLAWED. MOST OF THE CALLS WE GET AT Z-POWER ARE CONCERNING THE CHARGING SYSTEM.FROM DAY ONE KAWASAKI HAD A PROBLEM WITH THE ELECTRICS. APART FROM THE HEADLAMP BULB BLOWING PROBLEM, WHICH CAN ONLY REALLY BE CURED BY FITTING AN AFTER MARKET QUARTZ HALOGEN UNIT, THE MAIN CAUSE FOR CONCERN IS THE REGULATOR AND RECTIFIER. AT IT'S MOST BASIC THE FAULT CAN BE PUT DOWN TO POOR OR LOOSE CONNECTIONS. PARTICULAR ATTENTION MUST BE PAID TO THE GREEN AND WHITE PLUG CONNECTORS ON THE MIDDLE LOOM SECTION. THESE MUST BE CLEAN AND FREE OF ANY RUSTING.IF THE BATTERY IS NOT CHARGING THEN MORE OFTEN THAN NOT THIS WILL BE THE FAULT OF THE RECTIFIER. THIS IS THE UNIT WITH THE WHITE PLUG. MAKE SURE THE CONNECTOR PINS ARE CLEAN AND IF IT HAS A SEPARATE BLACK EARTH LEAD THEN THIS MUST BE CONNECTED TO EITHER THE CRANKCASES OR DIRECTLY TO THE NEGATIVE SIDE OF THE BATTERY. AN EASY CHECK IS TO TURN ON THE LIGHTS AND SEE IF THE LIGHTS BRIGHTEN WHEN YOU BLIP THE THROTTLE.IT IS QUITE COMMON FOR AN OWNER TO FORGET TO ATTACH THE RECTIFIER LEAD BACK ONTO THE BATTERY AFTER REMOVING THE BATTERY FOR CHARGING REASONS.IF THE BATTERY IS OVER CHARGING THEN IS NORMALLY THE FAULT OF THE REGULATOR. THIS IS THE UNIT WITH THE GREEN PLUG. AGAIN CHECK THE CONNECTOR PINS AND THE EARTH LEAD IF FITTED. THE USUAL SIGN OF OVER CHARGING IS A BOILED DRAINED BATTERY AND EXCESSIVE BULB BLOWING.NEEDLESS TO SAY, BOTH UNITS FAIL QUITE OFTEN AND UNLESS YOU WANT TO KEEP YOUR BIKE 100% ORIGINAL, THEN IT IS WELL ADVISED TO FIT AN AFTERMARKET COMBINED UNIT. A POPULAR MODIFICATION IS TO FIT A UNIT FROM A HONDA CB250 SUPERDREAM. DO NOT TELL ANYONE THAT YOU HAVE DONE THIS, OR YOUR STREET CRED WILL BE RUINED.!!

THE ALTERNATOR WINDINGS THEMSELVES ARE QUITE RELIABLE AND NORMALLY ONLY SUFFER FROM CRASH DAMAGE. THE ROTOR HOWEVER IS A BIT TROUBLESOME.THE INNER PART OF THE ROTOR CAN COME LOOSE FROM THE OUTER PART CAUSING PROBLEMS. THIS CAN EASILY BE CHECKED BY REMOVING THE LEFT HAND ENGINE COVER. ALSO, MAKE SURE IT HAS NOT SPUN ON THE WOODRUFF KEY THAT PEGS IT ONTO THE CRANKSHAFT. THE 8MM ROTOR BOLT CAN ALSO COME LOOSE AND MAY NEED REFITTING USING A LOCKING AGENT.

THE REST OF THE ELECTRIC'S ARE NORMALLY OK, BUT PAY ATTENTION TO THE MAIN WIRING LOOM WHERE IT RUNS AROUND THE LEFT HAND SIDE OF THE HEADSTOCK. CONSTANT MOVING OF THE HANDLEBARS OVER THE YEARS CAN CAUSE CERTAIN WIRES TO BREAK.

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THE INSTRUMENTS ON THE Z1 WERE DAMPED BY AN INTERNAL FLUID AND THIS FLUID CAN LEAK OVER A PERIOD OF TIME CAUSING THE NEEDLES TO FLUCTUATE WILDLY. THESE CLOCKS CAN NOW BE REFURBISHED AT A FRACTION OF THE COST OF NEW ONES.

THE REAR DRIVE CHAIN ON THE Z1 CAN SUFFER FROM UNEXPECTED SNAPPING. THIS CAN CAUSE EXCESSIVE DAMAGE TO THE INNER AND OUTER TRANSMISSION COVERS AS WELL AS THE CLUTCH PUSH ROD. PERIODIC CHECKING OF THE CHAIN IS ESSENTIAL TO ELIMINATE THIS COSTLY MISHAP FROM HAPPENING. ON THE SUBJECT OF TRANSMISSION, IT IS QUITE NORMAL FOR OWNERS TO FIT A PATTERN NON GENUINE FRONT SPROCKET WHICH DOES NOT HAVE A HOLE IN IT FOR THE LOCKING TAB WASHER. BE WARNED THIS CAN CAUSE THE SPROCKET TO FALL OFF CAUSING ALL TYPES OF UNTOLD DAMAGE. THE GEAR SELECTION IS USUALLY QUITE SLICK BUT WORN REAR CUSH DRIVE RUBBERS CAN CAUSE A SNATCH BETWEEN GEARS CHANGES. THE RUBBERS DO REALLY NEED TO BE CHANGED IF THERE IS MORE THAN 10MM OF MOVEMENT IN THEM.THE KAWASAKI TRADITION OF A LOUD CLUNK WHEN FIRST GEAR IS SELECTED IS QUITE NORMAL AND CAN BE VERY OFF PUTTING FOR THE FIRST TIME OWNER. THE REST OF THE GEARBOX WAS POSITIVE AND RELATIVELY NOISELESS. THE POSITIVE STOP BETWEEN FIRST AND SECOND WAS A GOD SEND AND MADE FINDING NEUTRAL SO EASY THAT IT MADE RIDING OTHER BIKES SEEM SUCH A PAIN. HOWEVER, THIS LABOUR SAVING DEVICE CAN CAUSE A LOT OF HEADACHES WHEN REBUILDING THE Z1 MOTOR ON THE BENCH. WHEN CHECKING THE GEAR CHANGE OPERATION, YOU CAN NOT MANUALLY SELECT SECOND GEAR WITHOUT THE ENGINE RUNNING AND OWNERS ARE SOMETIMES CONFUSED INTO THINKING THAT THERE IS SOMETHING WRONG WITH THE GEARBOX. WE HAVE HAD MANY CALLS AT Z-POWER BY WORRIED OWNERS, INCLUDING ONE CHAP WHO HAD STRIPPED AND REBUILT HIS BOTTOM END THREE TIMES BEFORE WE PUT HIM RIGHT. !!ALL THINGS CONSIDERED, THESE FEW SMALL NIGGLING FAULTS WERE EASILY ACCEPTABLE COMPARED TO THE PLEASURE THAT THE Z1 OFFERED.

THE Z1 MOTOR WAS OVER ENGINEERED BY KAWASAKI AND MANY TUNERS WERE QUICK TO NOTICE THIS. ALL SORTS OF BOLT ON GOODIES WERE AVAILABLE ALONG WITH SOME SERIOUSLY FAST AFTER MARKET PARTS. BIG BORE KITS RANGING FROM 998 UP TO 1260 WERE COMMON PLACE ALONG WITH MODIFIED CAMSHAFTS, VALVES, WELDED UP CRANKSHAFTS AND SMOOTH BORE CARBS TO NAME A FEW.THE MOST POPULAR BIG BORE KIT WAS TO 1015CC WHICH WAS THE STANDARD BORE SIZE OF THE LATER Z1000-A. ANYTHING BIGGER THAN 1070CC NEEDED NEW SPECIALLY MADE CYLINDER LINERS.INTERESTINGLY ENOUGH MOST TUNERS RECOMMENDED THE USE OF THE STANDARD CLUTCH AND CAM CHAIN, A TESTAMENT TO KAWASAKI'S ENGINEERING SKILLS.FOUR INTO ONE EXHAUST, ESPECIALLY NOISY ONES WERE THE BIG THING. THE CB750 HAD ALREADY KICK STARTED A GROWTH IN EXHAUST FABRICATION COMPANIES ALL AROUND THE WORLD AND NOW THE Z1 WAS ONE MORE REASON FOR THESE PIPE BENDERS TO GET EXCITED.KAWASAKI HAD MADE THE Z1 REASONABLY QUIET IN AN EFFORT TO APPEASE THE GROWING NUMBER OF LAWS COVERING NOISE EMISSION. MOST OWNERS THOUGHT THIS WAS MUCH TO QUIET. THE MARKET PLACE WAS SOON TO BE FLOODED WITH ALTERNATIVE EXHAUST SYSTEMS. MOST OF THESE WERE FOUR INTO ONE BUT THERE WAS ALSO A MARKET FOR FOUR INTO TWO SYSTEMS. OVER THE NEXT FEW YEARS QUITE A FEW FAMOUS NAMES CAME AND WENT. IN THE USA THERE WAS KERKER, JARDINE, RACER ONE, HOOKER TO NAME A FEW. HERE IN THE UK WE HAD PIPER, S+S, MOTAD, DUNSTALL AND LATER ON, ALPHA 41, HARRIS AND MICK GRANT SYSTEMS.AVAILABLE FROM OTHER COUNTRIES WAS DEVIL, SEBRING, MARSHALL, YOSHIMURA AND MARVING TO NAME A FEW. THE LIST WAS ENDLESS.MOST OF THE SYSTEMS ON OFFER WERE PRETTY USELESS OF COURSE. SURE THEY MADE YOUR BIKE SOUND FASTER BUT HARDLY ANY RESEARCH WAS CARRIED OUT BY THE MANUFACTURERS AND MOST BIKES SUFFERED SOME SORT OF FLAT SPOT SOMEWHERE IN THE REV RANGE. THE WEIGHT SAVING ALONE FROM THE STANDARD SYSTEM WAS THE BEST YOU COULD HOPE FOR. THE STANDARD OF THE CHROME FINISH WAS ALSO SOMETHING TO BE DESIRED. BUT HEY, THE SOUND OF A Z1 ON FULL SONG THROUGH AN EXHAUST WITH AN INCH OF BAFFLE IN IT WAS SOMETHING ELSE. THOSE WERE THE DAYS WHEN BIKES COULD BE SEEN AND HEARD. OTHER BOLT ON GOODIES RANGED FROM CHROME FINNED CYLINDER COVERS TO OIL PRESSURE GAUGES AND THE USUAL RANGE OF REAR SETS AND ACE BARS. ALL GUARANTEED TO MAKE

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YOUR BIKE 20% FASTER OF COURSE.! EVERYBODY KNEW THAT THE MORE SHOW THE MORE GO.!!

THE AFTER MARKET PEOPLE WERE NOT ONLY INTERESTED IN YOUR EXHAUST. THE REAR SHOCK ABSORBERS ON THE Z1 WERE AT BEST, ADEQUATE AND AT WORST DANGEROUS. THEY WERE SEVERELY UNDER DAMPED AND ONCE WARMED UP A WORRYING GYRATING EFFECT COULD BE FELT THROUGH THE REAR END.NO PROBLEM, KONIS, GIRLING, MARAZZOCHI, S+W TO THE RESCUE. UNLIKE THE EXHAUST THESE AFTER MARKET PRODUCTS WERE WELL WORTH WHILE. THEY DID INDEED TRANSFORM THE BIKE INTO A REASONABLE RIDE.OF COURSE FOR THE BETTER OFF CUSTOMERS, THERE WAS ANOTHER OPTION. A COMPLETE ROLLING CHASSIS KIT. IN THE UK WE HAD MANY FAMOUS FRAME MAKERS INCLUDING RICKMAN, TONY FOALE, SPONDON AND HARRIS. OTHER COUNTRIES HAD EGLI, BIMOTA AND MOTO-MARTIN AMONG OTHERS.THE RICKMAN BROTHERS MADE A COMPLETE BIKE EXCEPT FOR THE ENGINE, CARBS AND ELECTRIC'S WHICH YOU DONATED FROM YOUR NEW OR USED Z1. THIS MASTERPIECE SOLD WELL AND I WAS LUCKY ENOUGH TO BE HAVE BUILT QUITE A FEW OF THEM AT KNOTT MILL KAWASAKI WHO WERE AN OFFICIAL RICKMAN DEALER. THE OTHER GOOD THING WAS THAT WE WERE LEFT WITH MANY Z1/Z900/Z1000 ROLLING CHASSIS FOR US TO SELL OR REBUILD.THE RICKMAN WAS AN EXCELLENT HANDLING BIKE AND MADE GOOD USE OF THE Z1 POWER PLANT. EVENTUALLY THOUGH THE JAPANESE CAUGHT UP AND THAT WAS THE END. ONLY A FEW FRAME MAKERS SURVIVED INTO THE NINETIES.

AFTER MARKET WHEELS WERE ALSO POPULAR, CLAIMING TO BE LIGHTER AND EASIER TO CLEAN THAN THE STANDARD WIRE WHEELS. IN REALITY, UNLESS YOU SPENT A FORTUNE ON TRUE MAGNESIUM ITEMS, THERE WERE NORMALLY HEAVIER AND A PIG TO CLEAN WHEN THE ROAD SALT HAD TAKEN IT'S TOLL ON THEM. FAMOUS NAMES INCLUDED LESTER, CMA, DYMAG, DAYTONA, MELBER AND JOHN BROWN WHEELS. THEY WERE STYLISH AND COULD BE BOUGHT WITH WIDER RIMS INCLUDING A REAR SIXTEEN INCH OPTION FROM THE AMERICAN LESTER WHEEL COMPANY, THIS GIVE THE Z1 A CUSTOM CHOPPER LOOK WHICH WAS BECOMING VERY POPULAR IN AMERICA. UNFORTUNATELY SIXTEEN INCH TYRES WERE A BIT THIN ON THE GROUND HERE IN THE UK !!.IF YOU WERE NOT HAPPY WITH YOUR SEAT, THE BIKES SEAT THAT IS, YOU COULD ALWAYS CHANGE IT FOR A KING AND QUEEN TYPE SEAT OR AN INTIMATE 2+4 SPORTS SEAT. THERE WAS ALSO A WATER FILLED SEAT OFFERED !.THE OTHER AFTER MARKET PART THAT YOU HAD TO HAVE WAS A QUARTZ HALOGEN HEADLAMP CONVERSION. THIS MADE A LOT OF SENSE. THE ORIGINAL 40/45 WATT BULB WAS PATHETIC. THE CIBIE Z-BEAM WAS VERY POPULAR WITH RIDERS AND GIVE A RESPECTABLE 60/65 WATTS OF POWER. THE HEADLAMP RESISTOR THAT WAS FITTED TO THE LATER MODEL Z1 NEEDS TO BE DISCONNECTED TO MAKE PROPER USE OF THE IMPROVED HEADLAMP.

ANOTHER POPULAR MODIFICATION WAS THE USE OF ELECTRONIC IGNITION. THIS REPLACED THE STANDARD POINTS AND CONDENSER SET UP. THE Z1 DI NOT SUFFER FROM EXCESSIVE POINTS WEAR SO THIS KIT WAS MORE OF A PEACE OF MIND ITEM THAN NECESSITY. POPULAR KITS IN THE UK CAME FROM LUCAS, BOYER BRANSDEN AND PIRANHA.MANY IMPORT BIKES ARE FITTED WITH AFTER MARKET AIR FILTERS, USUALLY THE SEPARATE TYPE THAT CONNECT DIRECTLY TO THE BACK OF EACH CARB. UNLESS YOU WISH TO SPEND MORE TIME IN THE GARAGE THAN ON THE ROAD, THEN PLEASE GET RID OF THESE AS SOON AS POSSIBLE. THE STANDARD AIR BOX IS A MUCH BETTER PROSPECT THAN THESE TROUBLESOME FILTERS. AT BEST, THESE FILTERS, MAY GIVE YOU A SMALL INCREASE IN PERFORMANCE BUT MORE OFTEN THAN NOT THE JETTING WILL BE HARD TO SORT OUT AND YOU RUN THE RISK OF RUNNING THE BIKE WITH A WEAK MIXTURE SETTING CAUSING ALL SORTS OF PROBLEMS, THE WORST BEING A HOLED PISTON. IT IS SIMPLY NOT WORTH THE RISK.

KAWASAKI WERE QUICK TO SELL THE APPEAL OF THE Z1 TO A NEW BREED OF MOTORCYCLIST THAT WAS EMERGING AT THE TIME, THE LONG DISTANCE TOURER.DESPITE ITS DISADVANTAGE OF CHAIN DRIVE, IT WOULD BE SIX MORE YEARS BEFORE THEY OFFERED A SHAFT DRIVE VERSION, THE Z1 WAS AN EXCELLENT TOURER. THE MASSIVE TORQUE AND POWER COULD EASILY TAKE ALL YOU COULD THROW AT IT. MANY AFTER MARKET FAIRINGS, RACKS AND PANNIERS WERE AVAILABLE FOR THE Z1 FROM ALL OVER THE WORLD.

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IN THE UK WE HAD RICKMAN, TOWER AND BRITAX, WHILE IN AMERICA THE MOST FAMOUS MUST BE THE RANGE FROM THE VETTER COMPANY. THESE WERE DESIGNED BY THE MAN WHO GIVE US THE TRIUMPH HURRICANE AND WERE SO GOOD, THAT KAWASAKI THEMSELVES USED THEM AS AN OFFICIAL ACCESSORY OFFERING A COMPLETE KIT FOR LATER MODELS. THERE WERE MANY BMW OWNERS WHO WERE SWAYED TO THE KAWASAKI CAMP. THE Z1 WAS A LOT CHEAPER THAN THE BMW BOXER TWIN AND THE MONEY SAVED COULD BUY YOU LOTS OF KIT AND STILL PAY FOR THE HOLIDAY ITSELF. KAWASAKI WERE QUICK TO POINT THIS OUT AND SAID SO IN THEIR PRESS ADVERTISEMENTS OF THE TIME. THE Z1 WAS INDEED A BIKE FOR ALL MEN.ON THE SUBJECT OF MEN, THE Z1 WAS ALSO A BIG HIT WITH THE LADIES. NOT JUST AS A PILLION ON THE COMFORTABLE DUAL SEAT BUT ALSO AS A SUITABLE MACHINE FOR THEM. THE SHEER SIZE OF THE Z1 WAS PERHAPS A BIT OFF PUTTING BUT MANY A FEMALE WAS CHARMED BY THE SMOOTH TRACTABLE ENGINE AND THE RELATIVE LOW SEAT HEIGHT. AT A TIME WHEN PLATFORM BOOTS WERE RUNNING AT AROUND 6 INCHES HIGH, THE SEAT HEIGHT WAS NOT REALLY AN ISSUE.!ALL THINGS CONSIDERED, THE Z1 RANGE WAS AND STILL IS AN EXCELLENT ALL ROUND BIKE. IT IS A PITY THAT MORE EXAMPLES ARE NOT BEING USED AS AN EVERY DAY BIKE INSTEAD OF JUST SITTING IN SOMEBODY'S GARAGE AS A SHOW PIECE.

SO WHO, THESE DAYS, IS BUYING A Z1 ?. WELL WE HAVE SOLD THESE BIKES TO MANY DIFFERENT PEOPLE FROM MANY DIFFERENT WALKS OF LIFE. CUSTOMERS RANGE FROM THE 40 YEARS OLD "BORN AGAIN BIKER" TO THE 20 YEARS OLD PERSON WHO JUST WANTS IT BECAUSE IT STILL LOOKS GOOD. WE HAVE CUSTOMERS IN JAPAN, AMERICA, AUSTRALIA, SAUDI ARABIA AND ALL OVER EUROPE. THE APPEAL OF THE Z1 IS THE SAME THE WHOLE WORLD OVER.

WHEN CONSIDERING BUYING A Z1, THEN DO TRY TO TAKE ALONG SOMEBODY ELSE. NOT NECESSARILY A Z1 EXPERT BUT SOMEONE WHO WILL REALISTICALLY TELL YOU IF YOU ARE MAKING A BAD JUDGEMENT WITH YOUR HEART RATHER THAN WITH YOUR HEAD OR PERHAPS MORE IMPORTANTLY, WITH YOUR WALLET. !!REMEMBER THAT LIKE MOST OTHER MOTORCYCLES THAT ARE CONSIDERED TO BE CLASSICS, THE TRUE VALUE IS IN THE BIKES ORIGINALITY. IT IS NO USE SPENDING A SMALL FORTUNE ON A NON STANDARD BIKE JUST BECAUSE IT LOOKS VERY SHINY AND CLEAN. GO FOR THE BIKE THAT IS THE MOST ORIGINAL.TRY TO CHOSE A BIKE THAT IS ALL THERE EVEN IF SOME OF ITS PARTS ARE A BIT WORSE FOR WEAR. RENOVATION OF CERTAIN PARTS CAN BE CONSIDERABLY CHEAPER THAN REPLACEMENT PARTS. BASKET CASES SHOULD BE AVOIDED AT ALL COSTS. INVARIABLY ALL THE SMALL BUT EXPENSIVE BITS ARE USUALLY MISSING, TURNING A CHEAP BUY INTO A "MONEY PIT". TRY TO HEAR THE BIKE RUNNING IF POSSIBLE. IT TAKES A LOT TO STOP A Z1 FROM RUNNING. DO NOT LISTEN TO EXCUSES OF FLAT BATTERIES OR LOST KEYS. A Z1 MOTOR WILL RUN ON A WHIFF OF PETROL AND THE FLATTEST BATTERY, SO DO NOT TAKE NO FOR AN ANSWER. IF A POTENTIAL SELLER HAS SOMETHING TO HIDE THEN YOU CAN PRESUME IT IS SOMETHING DRASTIC. NON RUNNERS MUST BE TREATED WITH SUSPICION AND VALUED ACCORDINGLY.THE 1973 Z1 IS CONSIDERED TO BE THE MOST VALUABLE WHILE THE Z900-A4 IS CONSIDERED TO BE THE LEAST VALUABLE. THE HARDEST TO VALUE IS THE KZ900 LTD AND THE Z2. THEY SHOULD BE WORTH MORE BECAUSE THEY ARE CONSIDERABLY RARER, BUT THIS IS NOT ALWAYS THE CASE. REMEMBER BEAUTY IS IN THE EYE OF THE BEHOLDER AND IF THE LTD IS YOUR CHOICE THEN ONLY YOU CAN PUT A VALUE ON IT. THE Z2 MODELS SEEM TO BE WORTH AROUND 20% LESS THAN THERE Z1 EQUIVALENT. REMEMBER THAT THE VALUE OF ANY CLASSIC MOTORCYCLE CAN GO DOWN AS WELL AS UP AND I URGE ANYONE NOT TO BUY ANYTHING THAT STRETCHES THEIR FINANCES. NO MATTER WHAT MODEL YOU END UP WITH, REST ASSURED THAT THERE WILL BE A CHEAPER OR BETTER OR DEARER OR WORSE EXAMPLE JUST AROUND THE CORNER.!

CHAPTER TEN:

LIFE AFTER Z1 !.

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THE DECISION TO REPLACE THE Z900 WITH THE Z1000-A1 IN 1977 WAS NOT CONSIDERED TO BE ANYTHING BUT NATURAL PROGRESSION. IT IS ONLY NOW THAT WE CAN LOOK BACK AND SEE WHAT A MASSIVE CHANGE IT REALLY WAS.THE ONSLAUGHT OF BIGGER BORE BIKES IN THE MID SEVENTIES GIVE KAWASAKI NO OPTION BUT TO PRODUCE THE Z1000 BUT WITH HINDSIGHT THEY SHOULD HAVE CARRIED OUT MORE CUSTOMER RESEARCH INTO WHY THE Z1 RANGE WAS SO POPULAR. IF THEY HAD, THEN MAY HAVE REALISED THAT THE FOUR SEPARATE SILENCERS AND THE DRUM REAR BRAKE WAS A MAJOR SELLING POINT.INSTEAD THE Z1000-A1 CAME WITH A REAR DISK BRAKE THAT WAS VASTLY INADEQUATE IN THE WET AND A FOUR INTO TWO EXHAUST SYSTEM THAT WAS COSMETICALLY CHALLENGED, BUT OF COURSE WAS CHEAPER FOR THE FACTORY TO PRODUCE. THE PREMATURE FAILURE OF THE FOUR INTO FOUR SYSTEM WAS COSTING KAWASAKI QUITE AN AMOUNT IN WARRANTY CLAIMS SO THE MOVE TO THIS NEW SYSTEM WAS IN CERTAIN RESPECTS BETTER FOR THEM. HOWEVER THE TWIN SET UP WAS NO MORE RELIABLE, BUT PRESUMABLY CHEAPER TO REPLACE. THE PAINT WORK ON THE Z1000 WAS SOMEWHAT SUBDUED IN COMPARISON BUT KAWASAKI CLAIMED IT WAS CLASSIER. THEY WERE DESPERATE TO MOVE UPMARKET WITH THE Z1000 IN AN EFFORT TO SUSTAIN GROWTH IN THIS EVER INCREASING MARKET. THE DIAMOND WINE RED AND DIAMOND SKY BLUE, WHICH WAS ALMOST GREEN, WAS CONSIDERED BY MANY TO BE DRAB AND BORING.THE REST OF THE MAJOR CHANGES INCLUDED HANDLEBARS THAT NOW HAD THE SWITCH GEAR WIRES RUNNING THROUGH THE INSIDE OF THEM AND THE REPOSITIONING OF THE HAZARD LIGHT SWITCH TO THE LEFT HAND CLUSTER. THEY WERE NOW OPERATED BY THE PUSHING AND PULLING OF A SMALL RED SQUARE SWITCH. THE BATTERY BOX AND AIR BOX WAS ALSO REVISED WITH A MOVE BACK TO THE LARGER 14 AMP BATTERY.THE ENGINE WAS ALSO IMPROVED WITH A REDESIGNED CRANKSHAFT WHICH NOW HAD FULL CIRCLE CRANK WEBS IN AN EFFORT TO INCREASE SMOOTHNESS. POWER WAS UP TO A CLAIMED 85 BHP THANKS TO THE INCREASE IN CAPACITY AND REDESIGNED EXHAUST SYSTEM. 8 MM EXHAUST STUDS WERE NOW FITTED TO THE CYLINDER HEAD WHICH WAS A SMALL BUT SIGNIFICANT REVISION. THESE WERE MUCH MORE ROBUST THAN THE PREVIOUS 6 MM ITEMS.A SLIGHT CHANGE TO THE VALVES AND COLLETS FINISHED OFF THE MAJOR ENGINE MODIFICATIONS ALONG WITH MUCH THICKER OUTER ENGINE CASES. THIS WAS IN AN EFFORT TO REDUCE INTERNAL ENGINE NOISE. BY NOW THE COMPETITION WAS HOT ON THE HEELS OF KAWASAKI. HONDA WERE PRODUCING THE CB750F SERIES WHILE SUZUKI HAD NOT ONLY THEIR AGEING GT750 TRIPLE BUT NOW THE MUCH ACCLAIMED GS750 FOUR STROKE. THIS BLATANT COPY OF THE Z1 DESIGN NOT ONLY WENT WELL BUT IT HANDLED LIKE NO OTHER JAPANESE BIKE HAD EVER DONE BEFORE. THIS WAS A NEW ERA IN MOTORCYCLING AND KAWASAKI WERE, FOR THE FIRST TIME, CHALLENGED.YAMAHA HAD NOW MOVED INTO THE FOUR STROKE MARKET BIG TIME WITH THEIR EXCELLENT XS750 SUPER SHAFT TRIPLE AND THE ITALIANS WERE TEMPTING US WITH THE LAVERDA AND DUCATIS. THE CUSTOMER HAD NEVER HAD IT SO GOOD.KAWASAKI HAD RECENTLY INTRODUCED THE Z650-B1 AND MANY Z1 OWNERS WERE IGNORING THE BIGGER Z1000 AND PART EXCHANGING FOR THIS SMALLER BUT BETTER HANDLING MODEL. KAWASAKI HAD SHOT THEMSELVES IN THEIR OWN FOOT AND NOT EVEN REALISED. THE Z650 WENT LIKE A 750 BUT HANDLED LIKE A 500.

SALES OF THE Z1000-A1 IN 1977 WERE OK, BUT ONLY OK. THE END WAS NIGH !!.1978 SAW THE INTRODUCTION OF THE Z1000-A2. THIS WAS BASICALLY THE SAME EXCEPT FOR A COLOUR CHANGE AND THE FITMENT OF FLATTER HANDLE BARS.THE A2 WAS OFFERED IN LUMINOUS RED AND LUMINOUS GREEN, BOTH WITH GOLD STRIPING.THE FRONT CALLIPERS WERE REVERSED ONTO THE REAR OF THE FORK LEGS AND A NEW TRIANGULAR FRONT BRAKE MASTER CYLINDER WAS FITTED. THE PATTERN ON THE SEAT WAS SLIGHTLY ALTERED AND A NEW DIAPHRAGM FUEL TAP WAS FITTED. THIS STOPPED ANY PETROL FROM REACHING THE CARBS ONCE THE ENGINE HAD STOPPED RUNNING. THE CARBS WERE NOW FED WITH A SINGLE FEED INSTEAD OF THE PREVIOUS TWIN FEED.A MUCH LESS OBVIOUS MODIFICATION ON THE A2 MODEL WAS THE REMOVAL OF THE WOODRUFF KEY FROM THE LEFT HAND CRANKSHAFT TAPER AND A MOVE TO A BIGGER 10MM ROTOR BOLT. KAWASAKI HAD REALISED THAT THE CUSTOMER WAS NOW LOOKING FOR SOME THING A LITTLE DIFFERENT TO THE "UJM", THE "UNIVERSAL JAPANESE MOTORCYCLE". IN AN EFFORT TO

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SATISFY THIS NEED THEY PRODUCED THE Z1000-D1 OR Z1-R AS IT WAS BETTER KNOWN. THIS WAS A FACTORY CUSTOMISED Z1000.ITS ANGULAR STYLING WAS AN INSIGHT INTO WHAT THE JAPANESE HAD IN STORE FOR US IN YEARS TO COME. IT HAD SQUARE INDICATORS AND A CERTAIN ANGULAR CONCEPT TO IT THAT MADE IT LOOK SLIMMER AND SMALLER THAN THE Z1000-A.CAST ALLOY WHEELS WERE FITTED, REPLICAS OF THE MORRIS MAGS THAT WERE USED ON THE LTD RANGE, BUT STILL WITH AN 18 INCH REAR ITEM. THE FRONT WHEEL HOWEVER WAS ALSO A 18 INCH ITEM WHICH KAWASAKI CLAIMED TO IMPROVE HANDLING. IN FACT IT MADE IT MUCH WORSE.!!!A FOUR INTO ONE EXHAUST SYSTEM WAS FITTED AND FOR THE FIRST TIME ON A KAWASAKI ROAD BIKE, A FRONT FAIRING WAS FITTED COMPLETE WITH A SCREEN THAT WAS BLACKER THAN EVEN THE CHEAPEST SUNGLASSES !.A FUEL GAUGE AND AMP METER WAS ALSO INCLUDED, BOTH WILDLY INACCURATE OF COURSE.THE BRAKE DISK WERE NOW DRILLED WITH SMALL HOLES TO IMPROVE WET WEATHER BRAKING, BUT THIS WAS ALL IN VAIN.!THE ENGINE OF THE Z1-R WAS NOW FINISHED IN BLACK, JUST LIKE THE EARLIER 1973 Z1, BUT NOW THE FINISH WAS MUCH MORE DURABLE. BIGGER 28 MM CARBS INCREASED THE POWER OUTPUT TO 90 BHP AND MADE THE Z1-R THE FASTEST Z EVER. THE "R" BY THE WAY STOOD FOR "RACER". WISHFUL THINKING BY KAWASAKI OF COURSE.! IT WAS OFFERED IN ONE COLOUR ONLY, METALLIC STARDUST SILVER. A SORT OF LIGHT BLUE. THE RECENTLY INTRODUCED LIMITED EDITION Z650-C2 CUSTOM WAS ALSO OFFERED IN THIS COLOUR AS WELL.ALSO FITTED AS STANDARD, ON THE Z1-R, WAS SELF CANCELLING INDICATORS, HAZARD WARNING LIGHTS, DUAL SPRUNG REAR SHOCK ABSORBERS, QUARTZ HALOGEN HEADLAMP AND A CABLE OPERATED FRONT BRAKING SYSTEM THAT TOTALLY RUINED THE FEEL OF THEM. KAWASAKI DECIDED THAT THE Z1-R DID NOT NEED THE KICK START PEDAL ANY MORE, SO THEY PUT AN EMERGENCY NON FOLDING KICK START LEVER UNDER THE SEAT BOLTED TO THE SEAT BASE. A RUBBER BUNG COVERED THE KICK START SHAFT WHICH STILL PROTRUDED FROM THE CRANKCASES. IRONICALLY, THE Z1-R SUFFERED FROM THE ALTERNATOR ROTOR BOLT COMING LOOSE. THIS RESULTED IN THE STARTER MOTOR CLUTCH SLIPPING WHICH THEN NECESSITATED THE USE OF THE KICK START AFTER ALL!.THE SPECIFICATION WAS EXCELLENT BUT IT SOLD LIKE A LEAD BALLOON.!! MANY YEARS LATER IT WOULD BECAME A DESIRABLE CLASSIC. IT WAS OBVIOUS THAT KAWASAKI HAD BUILT A BIKE WELL AHEAD OF ITS TIME. THE WORLD WAS OBVIOUSLY NOT YET READY FOR A SQUARE Z1 !.

THE COMPETITION WAS NOW AT FULL SPEED. THE NEXT YEAR OR SO WOULD SEE THE INTRODUCTION OF THE GS1000, XS1100, CBX1000 AND MANY MORE EXOTIC SUPERBIKES. THE CHOICE WAS BECOMING INCREASINGLY HARDER.IT MAY BE HARD TO BELIEVE NOW, BUT THERE WAS A TIME IN LATE 1978 THAT UK DEALERS WERE STRUGGLING TO SELL A Z1000-A2 OR Z1-R. THE FLAVOUR OF THE MONTH WAS THE SUZUKI GS1000 AND IT HURT KAWASAKI REAL BAD. IN AN EFFORT TO INCREASE SALES KAWASAKI OFFERED A PAIR OF ALLOY SEVEN SPOKE WHEELS FOR THE Z1000-A2 TO SPRUCE IT UP AT A VERY REASONABLE £50 FOR THE PAIR. HOWEVER, IT DID LITTLE TO HELP SALES. THE WHEELS, BY THE WAY, ALSO FITTED THE Z750 B TWIN CYLINDER MODEL. MANY DEALERS MADE MORE OUT OF SELLING THE WHEELS THAN OUT OF THE BIKES THEMSELVES.

THE Z1000-A3 MK11 OF 1979 HELPED TO SAVE FACE AT KAWASAKI BUT FROM NOW ON IT WAS TO BE AN UPHILL STRUGGLE. INTRODUCED AT THE SAME TIME WAS THE Z1000-E1 SHAFT DRIVE. THIS WAS A FIRST FOR KAWASAKI AND WAS WELL RECEIVED.BOTH BIKES SHARED THE SAME 1015CC MOTOR WITH THE OBVIOUS ADDITION OF A BEVEL DRIVE ON THE SHAFT MODEL. A RETURN TO THE 28MM CARBS, LIKE THE ITEMS FITTED TO THE Z1-R, INCREASED POWER UP TO 93 BHP AND IMPROVED MID RANGE PULLING POWER. A VASTLY REDESIGNED AIRBOX ON THE SHAFT MODEL INCREASED MID RANGE POWER EVEN MORE. AN EXTRA TOOTH ON THE CRANKSHAFTS CAMCHAIN GEAR WAS FITTED ALONG WITH A LONGER 124 LINK CAMCHAIN AND A ONE TOOTH LARGER CAM SPROCKET ON EACH CAMSHAFT.TO REDUCE MAINTENANCE TIME AN AUTOMATIC TYPE CAM CHAIN TENSIONER WAS FITTED ALONG WITH TRANSISTORISED ELECTRONIC IGNITION.

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THE CAMSHAFT COVER WAS CHANGED FOR THE FIRST TIME EVER TO A SQUARE DESIGN MAKING THIS MK11 ENGINE INSTANTLY RECOGNISABLE. A MODIFIED CHARGING SYSTEM WAS FITTED ALONG WITH A SINGLE COMBINED RECTIFIER AND REGULATOR. AT LAST THE Z1 CHARGING SYSTEM HAD BEEN SORTED.THE OUTER ENGINE COVERS WERE ALSO GIVEN A NEW APPEARANCE BY THE USE OF FINNING ON THEM. OVERALL THE MOTOR WAS GIVEN A MUCH MORE ANGULAR DESIGN WHICH COMPLEMENTED THE REST OF THE BIKES APPEARANCE.THE BODYWORK OF THESE TWO BIKES WAS SQUARE WITH TRIANGULAR SIDE PANELS. THIS WAS CONSIDERED BY MANY TO BE A BAD MOVE AND NOT IN THE "z" TRADITION. THE A3 WAS OFFERED IN LUMINOUS DARK RED AND LUMINOUS DARK BLUE WHILE THE E1 WAS OFFERED IN LUMINOUS DARK RED AND LUMINOUS GREEN.KAWASAKI HAD BEEN WORKING ON A NEW BREED OF DISK PAD MADE FROM A SINTERED METAL COMPOUND WHICH WORKED QUITE WELL IN THE WET AND HAD INTRODUCED THEM ON THE 1979 Z650C3 MODEL. THEY ALSO HAD THE SENSE TO FIT THESE PADS TO THE A3 AND E1, IMPROVING BRAKING TO AN ACCEPTABLE LEVEL.THE SHAFT DRIVE BIKE SOLD WELL BUT IT WAS ECLIPSED BY ANOTHER KAWASAKI MODEL, THE MIGHTY Z1300 WATER COOLED SIX CYLINDER.THE Z1000 ST WAS LIGHTER AND CHEAPER THAN THE Z1300 OF COURSE, BUT NOT BY MUCH !. MANY CUSTOMERS WERE SPOILT FOR CHOICE BETWEEN THE TWO. THE AVAILABILITY OF A FULL TOURING KIT FROM KAWASAKI, FOR THE Z1000-ST, HELPED TO MAKE CUSTOMERS MINDS UP. THIS KIT WAS PRODUCED BY THE VETTER COMPANY OF AMERICA ESPECIALLY FOR KAWASAKI.THE Z1000-DI WAS STILL OFFERED IN 1979, BUT NOW A LARGER FUEL TANK AND A SINTERED METAL BRAKE KIT WAS OFFERED TO DEALERS IN AN EFFORT TO BOOST SALES. THESE WERE A DEALER FIT OPTION AND MANY DEALERS DID NOT BOTHER, PREFERRING TO SELL THE BIGGER TANK SEPARATELY IN AN EFFORT TO RAISE MORE CASH. NEEDLESS TO SAY, SALES DID NOT INCREASE BY MUCH AND WE WERE STILL SELLING THIS SAME MODEL IN 1981 !!!.KAWASAKI HAD ALWAYS HAD A POLICY OF NO DISCOUNTING ON THE WHOLE MODEL RANGE BUT IN 1979 THEY TURNED A BLIND EYE TO DEALERS DISCOUNTING THE Z1-R. SUCH WAS THE NEED TO SHIFT UNITS. THIS, TO MANY DEALERS, WAS THE START OF THE PRICE WAR THAT LASTED WELL INTO THE EIGHTIES. NOT UNTIL THE LAUNCH OF THE GPZ900R IN 1984 WAS IT POSSIBLE TO CHARGE, ONCE AGAIN, A FULL RETAIL PRICE FOR A NEW BIKE.

IN 1980 KAWASAKI OFFERED THE Z1000-A4 AND Z1000-E2. THESE TWO BIKES WERE MUCH THE SAME AS THE PREVIOUS YEAR EXCEPT NOW THEY BOTH WERE FITTED WITH QUARTZ HALOGEN HEADLAMPS, A REMOTE REAR MASTER CYLINDER RESERVOIR AND A SMALL KAWASAKI BADGE UNDER THE HEADLAMP. AS USUAL, DIFFERENT COLOURS FOR THE BODYWORK WAS ALSO OFFERED. THE A4 WAS OFFERED IN LUMINOUS RUBY RED OR LUMINOUS NAVY BLUE AND THE E2 WAS OFFERED IN RED OR BLACK.THE OTHER BIG NEWS FOR 1980 WAS THE INTRODUCTION OF THE Z1000-HI. THIS WAS BASICALLY A Z1000-A4 BUT FITTED WITH ELECTRONIC FUEL INJECTION WHICH INCREASED POWER UP TO A CLAIMED 96 BHP. IT WAS OFFERED IN ONE COLOUR ONLY, BLACK WITH GOLD WHEELS AND A PAINTED FRONT FENDER. MOST PEOPLE EITHER LOVED OR HATED IT.THE INJECTION SYSTEM USED ON THE H1 WAS ADAPTED FROM A BOSCH DESIGN PREVIOUSLY USED ON MANY GERMAN CARS AND WAS AT BEST TROUBLESOME AND AT WORST, DOWNRIGHT DANGEROUS. THE TRANSITION FROM CAR TO BIKE DESIGN WAS NOT A GOOD ONE AND MANY OWNERS DUMPED IT IN FAVOUR OF CARBS. VERY FEW WERE SOLD IN 1980 AND THE Z1000-HI WOULD PROVE TO BE A VARY RARE BIKE INDEED.

CUSTOMERS IN AMERICA WERE STILL BUYING THE "z" IN LARGE QUANTITIES AND APART FROM THE MODELS WE GOT HERE IN THE UK, THE YANKS HAD A FURTHER OPTION OF THE KZ1000-B LTD MODELS. THESE WERE BASICALLY CUSTOMISED VERSIONS OF THE STANDARD Z1000 WITH THE SAME MODIFICATIONS THAT THE KZ900-BI LTD HAD ENJOYED.THE Z1000-A2 OF 1978 WAS OFFERED TO AMERICAN CUSTOMERS IN AN ADDITIONAL COLOUR OPTION OF BLACK WITH GOLD STRIPING AS WELL AS THE STANDARD RED AND GREEN.IN THE MIDDLE OF 1978, KAWASAKI AMERICA OFFERED A LIMITED EDITION OF 200 OF THE KZ1000 MODEL AS A COMMEMORATIVE MODEL. THIS WAS KNOWN AS THE KZ1000-A2A. "THE SPIRIT OF AMERICA".

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IT WAS BASICALLY A KZ1000-A2 BUT FITTED WITH A FULL TOURING KIT MADE BY THE VETTER COMPANY. IT WAS FINISHED IN WHITE WITH RED AND BLUE STRIPES. THE PANNIERS WERE EMBOSSED WITH THE AMERICAN STARS AND STRIPES FLAG AND AN EAGLE LOGO, ON THE TOP OF THE TANK, STATED WHICH OF THE 200 MODELS IT WAS AND THE DATE WHEN IT WAS PRODUCED. CRASH BARS AND A LTD STEPPED SEAT FINISHED IT OFF. MEANWHILE, THE Z1-R WAS STILL PROVING TO BE A PROBLEM, NOT ONLY IN THE UK BUT IN THE STATES AS WELL.IN AN EFFORT TO REDUCE STOCKS, KAWASAKI IN CONJUNCTION WITH THE AMERICAN TURBO-PAK COMPANY OFFERED FOR SALE A LIMITED EDITION Z1-R TC. THIS WAS BASICALLY A STANDARD Z1000-D1 FITTED WITH A TURBO CHARGER SYSTEM. THE RESULT WAS THE ULTIMATE QUARTER MILE ANIMAL. KAWASAKI WENT TO GREAT EFFORTS TO POINT OUT THAT THERE WAS NO WARRANTY EXPRESSED, APPLIED OR GIVEN WITH THIS BIKE.!!. THIS BIKE PRODUCED ANYTHING FROM 105 BHP UP TO 145 BHP DEPENDING ON HOW MUCH BOOST PRESSURE THE OWNER DIALLED IN. ONLY A COUPLE OF HUNDRED WERE ORIGINALLY PRODUCED IN THE BLUE COLOUR WHILE LATER A CUSTOM BLACK WITH ORANGE, RED AND YELLOW STRIPES WAS OFFERED.I AM PRIVILEGED TO OWN ONE OF THESE MODELS WHICH MUST RANK AS THE ULTIMATE "Z". TOP SPEED IS AROUND THE 160 MPH MARK WITH ACCELERATION THAT IN ITS TIME WAS MIND WARPING. THE FACT THAT YOU ARE GOING AT THIS KIND OF SPEED ON AN OTHERWISE FAIRLY STANDARD Z1-R, WHICH NORMALLY STRUGGLES TO HANDLE 120 MPH, GIVES YOU MORE OF AN ADRENALINE RUSH THAN ANY MODERN HYPER BIKE COULD EVER GIVE YOU.!!!OF COURSE, ONCE YOU GET USE TO THIS RUSH, YOU CAN ALWAYS TURN THE BOOST UP JUST THAT LITTLE FURTHER !.

THE STANDARD Z1-R, WHILE NOT SELLING AS WELL AS KAWASAKI WOULD HAVE LIKED, DID SELL ENOUGH IN ITS FIRST YEAR TO WARRANT A NEW Z1000-D2 IN 1979.THIS WAS BASICALLY A MK11 VERSION OF THE Z1-R, WHICH AS WELL AS GETTING ALL THE MODIFICATIONS OF THE MK11, ALSO GOT A FOUR INTO TWO EXHAUST SYSTEM AND A RETURN TO A NINETEEN INCH FRONT WHEEL. IT WAS OFFERED IN TWO COLOURS, EBONY AND LUMINOUS DARK RED . IT RETURNED AGAIN IN 1980 AS THE Z1000-D3, THIS TIME IN EBONY ONLY.INSTEAD OF THE Z1000-H1 IN 1980, THE AMERICANS WERE OFFERED THE Z1000-G1. THIS WAS A FUEL INJECTED VERSION OF THE LTD MODEL AND WAS KNOWN AS THE "Z1 CLASSIC". IT WAS A LIMITED EDITION MODEL AND WAS MEANT TO COMMEMORATE THE LAST OF THE "Z1" LEGEND. IT CAME IN ONE COLOUR ONLY, EBONY WITH CHROME PANELS ON THE TANK.

FAMOUS FOR ITS APPEARANCE IN THE POPULAR TELEVISION SERIES "CHIPS" WAS THE KZ900 AND KZ1000 POLICE BIKES. THESE WERE ESPECIALLY MODIFIED BY KAWASAKI AMERICA AND KNOWN AS "c" MODELS. PAINTED IN THE USUAL WHITE LIVERY, THEY BECAME THE FIRST CHOICE FOR MOST POLICE FORCES IN THE STATES.MANY EXAMPLES HAVE FOUND THERE WAY TO THE UK, WHERE THEY ARE BEING RESTORED TO THEIR FORMER GLORY. THE LINCOLN PLANT STILL PRODUCES THEM TODAY BUT NOW WITH THE Z1000J SERIES MOTOR. THESE ARE KNOWN AS THE KZ1000-P MODELS.

SALES OF THE Z1-R IN EUROPE WAS ALSO POOR RESULTING IN KAWASAKI GERMANY OFFERING THE KZ1000-S. THIS WAS A STANDARD Z1-R FITTED WITH THE FOUR INTO FOUR EXHAUST SYSTEM FROM THE KZ900. THIS LIMITED EDITION MODEL SOLD QUITE WELL AND HELPED TO REDUCE SOME OF THE CONSIDERABLE STOCK.

1981 SAW THE INTRODUCTION, ALL AROUND THE WORLD, OF THE Z1000-J SERIES.THIS WAS A 998 CC MODEL WHICH MADE IT ELIGIBLE FOR THE UNDER 1000CC PRODUCTION CLASS IN RACING WHICH WAS BECOMING VERY IMPORTANT IN THE STATES. SUCH RACE SERIES KICK STARTED THE CAREERS OF RACING LEGENDS SUCH AS EDDIE LAWSON AND FREDDY SPENCER AND WAS THE BIRTH PLACE OF WORLD SUPERBIKES. THE Z1000-J IS CONSIDERED TO BE THE FIRST OF THE NEW GENERATION OF THE Z1 BLOOD LINE. WHILE STILL CONSIDERED TO BE A CLASSIC IN ITS OWN RIGHT, THE MANY ENGINE CHANGES MEANT THIS WAS THE END OF THE TRUE Z1. FROM THIS MODEL KAWASAKI WENT ON TO PRODUCE THE Z1000-R, GPZ1100, Z1100 SHAFT, Z1000-K/M LTD AND THE Z1100R1. EXCELLENT BIKES OF COURSE, BUT THEY NEVER ATTRACTED THE SAME FOLLOWING AND RESPECT THAT THE ORIGINAL Z1 DID.

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THE KING IS DEAD, LONG LIVE THE KING.