Page 16 - 2017-v.2-Part 4(EN)

TBIS 4210-4:2017

4.6.3 Track test method

4.6.3.1 Test track

a) Use an indoor test track if possible. If an outdoor test track is used, pay special attention to ambient
conditions throughout the test.

b) The gradient of the track shall not exceed 0,5 %. If the gradient is less than 0,2 % carry out all runs
in the same direction. If the gradient lies between 0,2 % and 0,5 %, carry out alternate runs in
opposite directions.

c) The surface shall be hard, of concrete or fine asphalt, and free from loose dirt or gravel. The minimum
coefficient of friction between the dry surface and the bicycle tyre shall be 0,75.

d) The track shall be essentially dry at the commencement of tests. When testing to the requirements
of 4.6.3.6, the track shall remain dry throughout the tests.

e) The wind speed on the track shall not exceed 3 m/s during the tests.

4.6.3.2 Instrumentation

The test bicycle or the test track shall be instrumented to include the following:

a) a calibrated speedometer or tachometer (accurate to within ±5 %) to indicate to the rider the
approximate speed at the commencement of braking;

b) a velocity-recording device (accurate to within ±2 %) to record the velocity at the commencement
of braking;

c) a distance recording system (accurate to within ±1 %) to record the braking distance;

d) a water spray system, to provide wetting of the braking surface, consisting of a water reservoir
connected by tubing to a pair of nozzles at the front wheel and a pair of nozzles at the rear wheel.
A quick-acting on/off valve shall be included for control by the rider. Each nozzle shall provide a
flow of water at ambient temperature of not less than 4 ml/s. Details of the positions and directions
of nozzles for rim brakes, hub brakes, band brakes, disc brakes, and back-pedal brake are given in
Figures 7 to 13;

NOTE Figures 7 and 8 for rim brakes show side-pull callipers but the same arrangements apply to centre-
pull callipers and cantilever brakes.

e) a brake-actuation indicating system to record independently when each lever or pedal is actuated.

4.6.3.3 Mass of bicycle, rider, and instrumentation

The combined mass of the bicycle, the rider, and the instrumentation shall be 100 kg.

When wet condition braking tests are performed, the combined mass can decrease throughout the test
due to water consumption, but it shall not be less than 99 kg at the end of the valid test runs.

Where a manufacturer specifies that their bicycle can carry a mass such that the sum of that mass plus
the mass of the bicycle is in excess of 100 kg (60 kg for young adults) to some value M, apply M as total
weight.

Any extra weight shall be positioned above the rear wheel and in front of the rear axle.

4.6.3.4 Force applied to the brake levers

a) Magnitude and position of force on brake levers

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