Troubleshooting

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Watts Troubleshooting

Spinner ® BLADE ION™

How is the user’s power measured by the Spinner Blade ION? The system measures the tangential (cross directional) force the brake pad applies to the Spinner Blade ION flywheel through a load cell. Knowing the tangential force component, the resulting restive torque, and the rider’s cadence, allows the computer to provide an accurate rider power output. Watts is a measure of the rider’s force sustained over a set distance and time. The Spinner Blade ION determines the rider’s Watts, by measuring the force at the flywheel with a load sensor. By monitoring the rider’s cadence at these loads, the computer can determine the rider’s power.

How do we validate the accuracy of the Spinner Blade ION strain gauge technology? We validate the accuracy through a comparison test, by measuring the difference between the input power to drive the bike compared to the resulting power output measured by the computer. We apply input power through a motor coupled to the crank, with a measurement device called a Dynamometer. The Dynamometer offers measurements with 99.5% accuracy (0.5% error). We compare this power input to the computer’s measured power output. By knowing the difference between the dynamometer power input and watts computer power output we can validate the accuracy of the system. The Spinner Blade ION is generally better than +/-20 watts from true watts values measured at the Dynamometer. Example: The actual watts value is 150 watts and the variance may be between 130 watts – 170 watts. Or, the actual watts value is 260 watts and the variance may be between 240 watts – 280 watts

Troubleshooting

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Basic Load Cell Test The first step to troubleshooting is to make sure there are no issues with the load cell. This can be done by performing the basic load cell test.

1. Remove the load cell cover (Fig. 1) from the brake block. 2. Turn the brake knob counter-clockwise to ensure there is no load on the brake pad.* 3. Start pedaling until the RPM reads between 90 – 95 RPM. 4. The watts computer should display a value of 18 – 25 watts.

*To ensure there is no load, you may need to pull up on the knob while testing. If the load cell readings are off, it will need to be replaced (PN: 070-1060).

Fig. 1

If the load cell reading is correct, yet in normal operation the watts appear to be incorrect, further troubleshooting will need to be done. There are mechanical factors that can affect the readings on the watts computer. To effectively troubleshoot watts issues, it is important to first understand what the issue is.

Possible Causes Watts Too High:

• Load cell cable is being pinched by the load cell cover.

• Brake pad spring angle is too large, causing brake to rest on flywheel and give some resistance when the brake

knob is at zero load position. Watts Too Low:

• Stiction in the load cell brake block assembly. Possible Cause for Sudden Jump*:

• Stiction in the load cell brake block assembly. *In the moderate to heavy resistance levels only.

Troubleshooting

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Sudden Watts Jumps in the No to Low Resistance Range Another symptom that may occur is a sudden jump in watts 20 – 80 watts at low resistance levels. Example is that the watts value does not increase as the rider applies tension through the brake knob until a certain point when the watts value suddenly jumps. Note: When there is no to low resistance on the brake pad, the difference in watts readings may vary greater than +/- 20 watts. This is normal. As the rider applies more resistance, the variance will decrease. If a sudden jump occurs in the moderate to heavy resistance levels, troubleshooting should be done.

Load Cell Cable Pinched If the load cell cover is too tight, it will pinch the cable (Fig. 2). This will cause faulty readings from the load cell. Loosen the 3 screws (Fig. 3) to the point where the cable is not being pinched.

Fig.2

Fig. 3

Troubleshooting

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Checking the Brake Spring Angle 1. Remove the brake pad assembly and check the angle of the brake spring against the template* (Fig. 4). If the

angle does not match it will need to be corrected.

*Be sure to print the template from this document and have available.

Fig. 4

2. The spring will need to be adjusted to the correct angle using clamp pliers (Fig. 5). Bend the spring to match the

angle of the template (Fig. 6).

Fig. 5

Fig. 6

Troubleshooting

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Troubleshooting

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Faulty Load Sensor If the brake spring angle is correct and (with no load on the brake), yet the watts reading is still high, the load cell is faulty and should be replaced. PN: 070-1060

Stiction in the Load Cell Brake Block There are a few areas to check for stiction in the system:

• Brake spring angle is too small, causing the brake pad to push against the brake rod end with a large force (refer to “Checking the Brake Spring Angle on page 3).

• Dry master link and brake knob groove.

• Oversized plastic master link (length) bushings.

• Undersized plastic master link bushing holes. Lubricating the Load Cell/Brake Knob Groove

1. Remove the load cell assembly cover (Fig. 7). Then remove the master link locking clips and plates (Fig.8).

Fig. 7

Fig. 8

2. Remove the two master links completely (Fig. 9).

Fig. 9

Troubleshooting

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3. Apply bike grease (Spintech Fitness Equipment Grease with Teflon) to the brake knob groove (Fig. 10). Then reinstall

the brake pad assembly.

Fig. 10

4. Apply grease to the shafts of both master links (Fig. 11).

Fig. 11

5. Reinstall the master links, master link clamps and load cell assembly cover.

Troubleshooting

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Checking the Plastic Bushings There are 4 plastic bushings in the load cell brake block (Fig. 12).

Fig. 12

The first thing to check is the length of the plastic bushings. They should be slightly sticking out of the brake block (Fig. 13).

The width of the bushings should be between 17.0mm and 17.4mm (Fig. 14). If they are outside this range, the block

assembly should be replaced. PN 740-8348-KT

Fig. 13

Fig. 14

Troubleshooting

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Also verify that the hole in the plastic bushings are not undersized. The master link should move freely once inserted into the bushing. To test, place the master link in the plastic bushing at a 45 degree angle (Fig. 15). When you let go of the master link, it should fall on it’s own. If the master link does not move, then the bushing hole is too small and the brake block assembly should be replaced. PN 740-8348-KT

Fig. 15