Page 34 - TBIS_79010-2019_(EN)_1nd

TBIS 79010:2019

b) If an adaptor assembly is used (as shown in Figure 10), 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 F 2 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 6 and Figure 10 —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 6 — Forces on pedal-spindle
Force in N
Force, F 2 1200

B-B

Figure 10 — Frame and front fork assembly (Multi-lane): fatigue test with pedalling

forces

Page 30 for 43