Page 32 - TBIS_79010-2019_(EN)_1nd

TBIS 79010:2019

downwards at an angle of 45° (accurate ± 2,0°) to the horizontal and secure the front
end of the chain to the middle chain-wheel of three, the smaller chain-wheel of two,
or the only chain-wheel. Attach the rear end of the chain to the rear axle and
perpendicular to the axis of the axle.

b) If an adaptor assembly is used (as shown in Figure 9), ensure that the assembly is
free to swivel about the axis of the bottom-bracket and that both replacement arms
are 175 mm long (L) and that they are both inclined forwards and downwards at an
angle of 45° (accurate ± 2,0°) to the horizontal. Secure the position of the crank
replacement arms by a vertical arm (which replaces the chain-wheel) and a tie-rod

which has ball-joints at both ends and which is attached to the rear axle
perpendicular to the axis of the rear axle. The length of the vertical arm (Rc) shall be
75 mm and the axis of the tie-rod shall be parallel to and 50 mm from the vertical

plane through the centre-line of the frame.
Subject each pedal-spindle (or equivalent adaptor component) to a repeated

downward force of F1 at a position 150 mm from the centre-line of the frame in a
vertical, transverse plane and inclined at 7,5° (accurate to within ± 0,5°) to the
fore/aft plane of the frame as shown in Table 5 and Figure 9 —During application of

these test forces, ensure that the force on a “pedal-spindle” falls to 5 % or less of the
peak force before commencing application of the test force to the other
“pedal-spindle”.

Apply the test forces for 100 000 test cycles where one test cycle consists of the
application and removal of the two test forces. The maximum test frequency shall be

maintained as specified in 4.1.1.5.

Table 5 — Forces on pedal-spindle
Force in N
Force, F 1 1200

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