Page 41 - 20190101 part 6 (EN)

TBIS 4210-6:2019
Annex G
(normative)

Safety test of composite fork stem (fork steerer)

G.1 General
1. The test method of the item is applicable to all composite fork defined in TBIS 4210.
2. The tightening conditions of the fork stem and handlebar-stem assembly should be
finished according to the setting values of the manufacturer.

G1.1 Requirements:
After the test is finished according to the method specifically described in G1.2, there
should be no fracture in the fork stem; in the fatigue test, the running displacements
(peak-to peak value) at the points where the test forces are applied shall not increase by
more than 20% of the initial values.

G1.2 Test method:
1. The tightening conditions of the fork stem and handlebar-stem assembly should be
finished according to the setting values of the manufacturer (have to match the head tube
angle of the frame). Apply a torque 240 Nm about the centerline of the fork stem and
maintain for 1 min

Figure G1 Torque to the fork steerer

2. After the torque to the fork stem, and continue the fatigue test as TBIS 4210-5 Sec. 4.9
with the same assembly of fork stem and handlebar stem assembly.

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