Ride Drive Driving Tips Effective Braking Techniques

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ffective Braking Techniques

he brakes fitted to your car will perhaps be something you take very much for granted. After all, when

u recognise the need to lose speed quickly, you just lift off the gas, put your foot onto the brake pedal

d the car slows down. Nothing to it is there? However, why is it, when you do that, does the car slow

stop? What’s going on underneath you?

ou may not quite have thought of it like this, but when you apply your brakes, even when they are

orking at maximum efficiency, they will only be able to slow your car at a rate according to the

mount of grip available from your tyres. Why? Because the tyres are the only part of your car that is in

ntact with the ground, and if things were any different, we would all be able to get 100% braking

fect 100% of the time, even when driving on ice!

yre grip is caused by friction,

nd friction between tyre and road is caused by down force

akes use tyre grip to slow and stop the car, and tyres get their ability to grip the road from something

lled friction, which in turn, is provided by down force. A road car gets its down force from gravity, as

is the mass of that vehicle acting downwards onto the road surface that provides tyre grip. Therefore,

you have a car that weighs 1,000kgs, and let us say that weight is evenly distributed within the

hicle, you will have 250kgs of down force acting on each of the four wheels, creating equal friction

tween each tyre and tarmac.

he problem is you cannot drive a car without there being a constant variation in the amount of

wnforce applied to any of the four tyres, which of course will vary according to what the car is doing

y given time. When you apply your brake pedal, and whilst driving forward, there becomes ancreased amount of down force at the front of the car.

he car doesn’t lose any of its overall weight, it’s just there is now a variation in the distribution of the

erall amount of downforce available. Whatever the total amount of down force, it all has to be shared



tween the four tyres.

Why bigger and more powerful brakes are fitted to the front of the car

his is why bigger and more powerful brakes are fitted at the front wheels, as compared to those at the

ar. Under braking the front tyres will give you better road adhesion, when compared to those at the

ar, so it makes sense to create the most braking force where there is the most tyre grip. With less

wn force at the rear, any substantial braking going on at that end of the vehicle would easily result inwheel lock–up situation.

aking systems fitted to cars, and light to medium weight goods vehicles, are operated by hydraulics

a a series of small–bore tubes (brake pipes) filled with fluid connecting the action of the brake pedal

the brake units fitted to each wheel.

o overcome the problem of increased downforce at the front, and decreased down force at the rear,

nder braking, there is a pressure limiting valve built into the system that will detect the differencetween the front and rear loading, and will compensate by adjusting the balance in braking power

cordingly to prevent rear wheel lock–up.

ow to Get Better Performance From Your Car Brakes

hilst the effectiveness of the vehicle brakes is limited by the maximum amount of available tyre grip,

tter braking performance can be realised by applying the brakes in an intelligent manner.

here will be many who have travelled as a passenger in car and perhaps wished they had remembered

bring a surgical collar with them. You know the type of driver? The one who just pokes at the brake

dal, separating your vertebrae every time they slow the car down, or who will leave braking very late

that your eyeballs jump from their sockets due the terrific rate of deceleration. Very often, what

ould be a gentle process, becomes an eye–popping and rather hurried almost emergency stop.

ough handling of the car causes accelerated wear

nd diminishes your control potential

part from being very uncomfortable, and there being an enhanced risk of skidding or control loss, it is

uite harmful to treat a car in this way. Think about the stress that type of abuse places upon the

spension linkages, the brake components and even the engine mountings. Yes, the engine mountings

and the gearbox too, for that matter.

very time you snap the brakes on in a rough manner your engine and gearbox are trying to jump out

rough your radiator grille in just the same way all that stuff you have dumped on your back seat flies

rward onto the floor. Make no mistake, there is a lot of stress going on there.

or the highest level of braking performance, apply them progressively and when the vehicle is



avelling in a straight line. Straight line braking ensures the most satisfactory distribution of

wnforce. Whilst is if not possible under these conditions to give each tyre a whole 25% of what is

ailable, if you can apply the loading over matched pairs of tyres in an equal manner, that is the best

mpromise you can wish for.

nder braking, you will need to match loading between the front tyres, which means by default you

ll have matched loading between the rear tyres. By applying the brakes with empathy, you will create

aximum vehicle stability under braking and realise the maximum level braking performance for the

nditions.

rogressive Braking Gives Better Stopping Power

o apply progressive braking, firstly rest your foot on the pedal and gradually increase the pressure

ntil the desired amount of braking effect is achieved. Once your speed has been reduced sufficiently,

e procedure is then completed in reverse, i.e. you release the pressure on the pedal in the same

ogressive manner.

aking should be pooh–shaped. That is to say it should be tapered at both ends and fat in the middle.

is amazing how the thought of this creates a much smoother driving technique! Braking should be

mmenced early to give time for smoothness, but that can only be achieved by good quality distance

servation, well–developed anticipation skills and effective advanced planning.

aking whilst cornering will immediately put the car off–balance, as the front tyres of the vehicle will

come more heavily loaded, and because you are steering, the extra loading becomes biased to one

ont corner. This is one heck of a load for one suspension unit to cope with, and it creates a great deal

extra work for one tyre to have to cope with too.



hen brakes are applied in a bend,

rticularly with front wheel drive

hicles, not only do the tyres at the rear of

e car have less down force available, but

hat they do have becomes unevenly

stributed. This makes it even more

fficult for the back tyres to grip the road.

ue to the effect of cornering the rear of

e vehicle wants to swing out to vertake

e front. Applying the brakes whilst

rnering can even cause the rear tyre on

e inside of the curve to lose contact with the road altogether, as vividly illustrated in this photograph.

nother product of braking into a bend is that due to momentum, the car will be more intent onushing straight ahead, instead of changing direction as you intended. If you don’t get the oversteer

uation, as mentioned above, you will certainly experience understeer.

he Actions of The Average Motorist

aving read this series of articles about advanced methods of driving you will no doubt begin to notice

w the general motoring public deal with bends and corners. The usual pattern is to decelerate, brake

d to change down through the gearbox, all whilst steering around a bend, completing all these

tions at the same time. In fact, the huge majority of drivers will only reach the most appropriate

ad–speed for a bend, and have selected the appropriate gear, no earlier than the half–way point of

mpleting the bend.

he effect is very unkind to the car, as well as being uncomfortable for anyone on board, because as

on as the foot is lifted from the gas, and⁄or the brakes are applied, the balance of the vehicle changes,

the emphasis on down force becomes biased towards the vehicle front. With steering being applied

well, this will create greater potential for things to go wrong, and not only that, but it knocks hell out

the tyres too.

rivers who brake into corners will scrub away the outer shoulders of their front tyres and won’t get

ywhere near the mileage they could from them. They also accelerate the amount of wear and tear

at occurs within other component parts, such as suspension units, causing increased maintenance

d repair costs.

he Effective Method in Braking For Bends

he most effective way to deal with braking for bends is to firstly bring down the speed of the car until

u are happy it is appropriate to complete the bend you are about to enter, and whilst still travelling



a straight line. Having settled the car to the speed required, now directly select the most suitable

ar to provide the necessary response relative to the speed at which you are travelling — again before

u start to turn into the bend.

y these means, at the time you begin steering into the bend, you will are travelling at the right speed

d with the right gear engaged (we won–t go into the topic of positioning here, as that would over–

mplicate matters for now).

hen you actually take the car around a bend, apply just enough throttle to keep the engine pulling,

ut without the car accelerating. By these means you will achieve the best situation in terms of vehicle

ability, particularly as the loading of down force will be matched between the two tyres along the

utside of the curve, and between the two tyres on the inside.

hen descending a winding hill, apply firm braking when the car is travelling straight, even

aggerating the amount of speed loss required before the bend is reached, and then apply lighter

ake pressure around the curves as required. Also, try to use only one brake application per task, as

ot only does this form one of the key elements of The System of Car Control, a subject to be dealt with

a later chapter, but it also helps a driver to become more disciplined in searching out actual or

tential danger.

lian Smith Ride Drive Limited

WARNING – This series of driving tips articles has been made available to you to read, and if you

sh, to print or save, and you may do so completely free of charge. However, this permission is given

here the material is for personal use only. Any reproduction, copying or publishing for any form of

rsonal gain, financial or otherwise, or for any form of distribution, without prior permission, will not

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en extended to our site visitors in producing this material. If you are unsure as to whether yourtended use of this, or any other written article that you find published on this website, will be

fensive, please ask for guidance.

ake Your Comment

Part–1 Effective Braking Techniques

Part–2 How a Car Braking System Works

Part–3 Vehicle Stopping Performance


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ffective Braking Techniques

BS The Limitations & The Advantages

hat do you know about ABS? How do you use ABS properly? Have you ever experienced ABS when

been working? What do the letters A–B–S actually stand for?

kay, let’s start with that name, ABS. It stands for Antilock Braking System, and what that means is

at no matter how hard a driver may stamp on the brake pedal, the road wheels are never supposed

ck into a skid, which for most driving conditions is true.

o How Does It Help, Not Locking The Wheels?

ell, for a start, you need to understand that each of your vehicle tyres has one allocation of grip, and

t us say that overall it is 100%. What you also need to understand is that whatever the demand you

ace upon that tyre you are going to use up some of that grip–allocation. Whatever is left will be the

tal amount available to use for other tasks.

onsider this. For cornering purposes, if you are using 80% of the grip–allocation to get your vehicle

ound a bend, you will only have 20% left for braking – or any other task for that matter.

aking the above into account, and when driving a car not equipped with ABS, if you brake so hard, or

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harshly, as to lock your wheels into a skid,

u have none of your grip allocation left with

hich to change direction, because the

idding tyre has used it all up. Simply you

ve nowt left for steering. And that’s what

BS is all about.

BS V’s Raw Skill

BS was introduced, primarily, to cover up for a lack of driver skills, and this was (and still is)

cessary as almost every driver, when faced with an emergency that required both urgent loss of

eed and change in direction, would crash into whatever it was they were trying to avoid. This is

cause the instinctive reaction for nearly all will always be to try and press the foot through the floor

hilst vainly heaving on the steering wheel with all their might to avoid impact. All to no avail.

With ABS there is no locking of wheels

nd therefore some directional control is still available.

, the primary benefit of ABS, for normal road surfaces, is to increase the ability of the driver to

aintain control of the vehicle, rather than go into a skid. Despite this, loss of control still remains

kely on loose surfaces, like gravel, or slippery surfaces like snow or ice. On a very slippery surface,

ch as sheet ice, poor wet road surface, it is possible to lock multiple wheels at once, and this can

feat ABS, which relies on detecting individual wheels locking.

hreshold Braking

his is a term that some readers may well be aware of, and describes the technique where a driver

nely calibrates the amount of brake pedal pressure to apply, so as to maintain a degree of braking

fect at the wheels that is but a hair’s breadth inside the point of wheel lock–up. Thhis is finding the

reshold between a rotating wheel under braking and a locked wheel under braking.

is well reported that Lewis Hamilton, current Formula One world champion, has a particular skill for

nowing where the braking threshold of his car will be at any time and in any conditions, and this has

en one of the elements leading to his success. He is well in tune with his car and is able to work with

well.



owever, the availability of the ABS of a vehicle should not deter drivers from learning to master

reshold braking, as driver will tune to machine more accurately this way. As already noted above, the

aximum braking effect is achieved when the tyres are at the limit of friction. ABS works by releasing

e brakes as the tyres break traction, so a skilled driver, who is in tune with their car, should be able to

ceed the braking performance of an ABS system under most circumstances.

BS – The Pedal Will Pulse & Vibrate

hen activated, the ABS causes the brake pedal to pulse or vibrate, which is very noticeable, and this is

e partial release and reapplication of braking effect at the wheels many times per second. As most

ivers rarely or never brake hard enough to cause the system to activate, and a significant number

rely bother to read the manual of the vehicle they drive, the effects may not be discovered until a real

mergency is encountered.

is usually during an emergency when a driver will encounter the pulsing of the pedal for the first

me. Many will react by reducing pedal pressure and thus lengthening braking distances, contributing

a higher level of road collisions than the stopping capabilities of ABS would otherwise promise. In

ort, many driver’s first time experience of the rumbling pedal is quite alarming.

he recommended technique for non–expert drivers, when in a typical full–braking emergency and

ing an Antilock Braking System, is to apply maximum brake pedal pressure and maintain it, whilst

eering to avoid collision as necessary. This is the one for all solution to most situations, but to do this

fectively training will be required.

on’t wait for a real emergency before you experience the sensation through the pedal, but try it out in

ntrolled circumstances first, and then come the time you have to use it, the sensation won’t come as

ch a shock. Perhaps in an empty car park, on a quiet country lane, on some private land, but only do

at very low speed, and when there is no one else around to be caused alarm.

horter Braking Distances

already stated, driving on high–traction surfaces, such as bitumen or concrete, whether wet or dry,

non ABS–equipped car, depending upon who is the driver, will be able to attain braking distances

tter (i.e. shorter) than those that would be easily

ssible with the benefit of ABS.

n alert and skilled driver without ABS should be

le, through the use of techniques like threshold

aking, to match or improve on the performance

a typical driver with an ABS–equipped vehicle. However, for a majority of drivers, in most

nditions and in typical states of alertness, ABS should at least reduce their chances of a pile up, or

duce the severity of impact if nothing else. At least that’s the theory.



arget Fixation

arget fixation is where a driver, fearing he or she will hit something, actually ends up locked on to it,

d as a consequence, WILL hit it! It’s an ‘old brain’ function. I remember Julian of Ride Drive, during

discussion on this topic, told me how he, when in his previous role as a traffic patrol police officer,

d actually seen this happen for real on the public roads and how he had investigated collisions

ading up to which a driver had ‘chased’ the victim across the road to the point of impact.

rstly, be aware of Target Fixation, as the only way you will overcome this is through training. I

perienced this myself with a group of others during a training exercise. Initially there was a 100%

ilure rate, and I had excellent skid control experience already!

condly, ABS should have significantly reduced the chances of a skid and subsequent loss of control

d yet all of us crashed into what we were trying to avoid. However, to master the extra steering input

quired to turn the vehicle under ABS, again there was 100% failure rate within the group.

BS Can Increase Braking Distances

owever, on gravel and in deep snow, ABS tends to increase braking distances, not reduce them, but

hy? On these surfaces, locked wheels dig into the gravel or snow, building up a wedge of material

ead of the tyre, which helps to slow the vehicle more quickly. ABS prevents this from occurring.

me ABS calibrations reduce this problem by slowing the cycling time, thus letting the wheels

peatedly briefly lock and unlock, which is better, but not ideal.

me manufacturers have therefore implemented something called Brake Assist systems that

termine if the driver is attempting a panic stop and will maintain braking force in this situation.

evertheless, ABS can significantly improve safety and control for drivers in on–road situations if they

now not to release the brakes when they feel the pulsing pedal.

ehicles equipped with braking systems without ABS have been shown to out brake vehicles equipped

th ABS, and the British car magazines Evo and Autocar both conduct periodic tests of vehiclesmparing their ability to accelerate from a standing start to 100mph, and then brake to a stop. This is

e so–called 0–100–0 test. They repeatedly find that the cars without ABS will outperform

mparable cars equipped with ABS.

he biggest advantage that ABS has over a non–antilocking system is the modern ABS systems will

mpensate for each of the four tyres being on four different surfaces. In this scenario the system will

onitor and apply different degrees of braking pressure to each wheel according to the level of tyre

hesion available. This is something a human controlled non–antilock system can’t achieve, as with

e non–ABS vehicle, the maximum overall braking effect will always be limited by the one tyre out of

ur that is experiencing the lowest level of grip.



there you have it. ABS is great for many situations, but not the answer to all. And, to get the best

om it you need some training. Otherwise it just remains a Marketing Point in a glossy sales brochure.

WARNING – This series of driving tips articles has been made available to you to read, and if yoush, to print or save, and you may do so completely free of charge. However, this permission is given

here the material is for personal use only. Any reproduction, copying or publishing for any form of

rsonal gain, financial or otherwise, or for any form of distribution, without prior permission, will not

tolerated and will be considered as a breach of copyright. Please do not abuse the good faith that has

en extended to our site visitors in producing this material. If you are unsure as to whether your

tended use of this, or any other written article that you find published on this website, will be

fensive, please ask for guidance.

ake Your Comment


Part–2 How a Car Braking System Works

Part–3 Vehicle Stopping Performance


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ehicle Brakes – Part–Four

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