Page 42 - TBIS_15194-2019_(EN)_3nd

TBIS 15194:2019

Repeat the procedure (applying the operating force determined as above accurate to
within ± 5 %) 10 times, or, with more repetitions if necessary, until the mean braking
force from anyone of the three latest tests does not deviate by more than ± 10 %
from the mean braking force from these same three tests.

c) The performance tests
1) Testing under dry conditions

For hand operated brakes, with a vertical force applied to the bicycle sufficient to
prevent skidding of the tyre on the wheel under test, accelerate the driving
mechanism to the specified velocity, then apply the operating-force in a series of 20
N increments from 40 N to either 180 N(in case of young adult bicycles, apply to 120

N) or to the force necessary to achieve a braking force of at least 700 N, whichever is
the lesser. However, if the wheel locks, if any possible brake-overload device is
actuated, or if the hand-lever comes into contact with the handlebar, do not
increase the force further. For each increment of applied operating force, perform

three tests within 1 min. Before applying the next level of operating force, allow the
brake to cool for 1 min.
For back-pedal brakes, with a vertical force applied to the bicycle sufficient to

prevent skidding of the tyre on the wheel under test, accelerate the driving
mechanism to the specified velocity, then apply the operating-force in a series of 50
N increments from 100 N to either 350 N or to the force necessary to achieve a

braking force of at least 400 N, whichever is the lesser. However, if the wheel locks,
if any possible brake-overload device is actuated, do not increase the force further.
For each increment of applied operating force, perform three tests within 1 min.
Before applying the next level of operating force, allow the brake to cool for 1 min.

The applied operating forces shall lie within ± 10 % of the intended operating forces,
shall be applied as specified in Figures 5 and 6 and 4.3.5.9.5.3 c), shall be recorded
with an accuracy of ± 1 %, and shall be fully applied within 1,0 s of the

commencement of braking.
For each increment of operating force, record the braking force value, FBr rec, for a
period of between 2,0 s and 2,5 s, with measurement starting 0,5 s to 1,0 s after the

commencement of braking. Record FBr rec as the average braking force during this
measurement period.

The time at which the measurement of the braking force is started shall be related to
the speed at which the operating force is applied. If the operating force is fully
applied in less than 0,5 s after the commencement of braking, start the
measurement after 0,5 s. However, if the operating force is fully applied between 0,5

s and 1,0 s after the commencement of braking, start the measurement when the

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