Page 20 - 2018-v.3-Part 2(EN)

Table 4 — The values of steering angle

Angles in degrees

City and trekking Young adult bicy-
Bicycle type bicycles cles Mountain bicycles Racing bicycles
Steering angle 60 60 30 30
θ 1

4.7.6 Steering assembly — Static strength and security tests

4.7.6.1 Handlebar stem — Lateral bending test

4.7.6.1.1 General

This test is intended for stem manufacturers who do not produce handlebars.

4.7.6.1.2 Requirement

When tested by the method described in TBIS 4210-5:2016, 4.2, there shall be no cracking or fracture
of the stem and the permanent deformation measured at the point of application of the test force and in
the direction of the test force shall not exceed 10 mm and record the ratio between weight and rigidity
in the test result..

Handlebar stems can influence test failures of handlebars but handlebars do not usually influence test
failures of stems. For these reasons, a handlebar is always to be tested mounted on a stem but stems can
be tested with a solid bar in place of a handlebar.

4.7.6.2 Handlebar and stem assembly — Lateral bending test

4.7.6.2.1 General

This test is for manufacturers who produce handlebars and stems or for cycle manufacturers.

4.7.6.2.2 Requirement

When tested by the method described in TBIS 4210-5:2016, 4.3, there shall be no cracking or fracture
of the handlebar, stem, or clamp-bolt and the permanent deformation measured at the point of
application of the test force shall not exceed 15 mm and record the ratio between weight and rigidity
in the test result..

4.7.6.3 Handlebar-stem — Forward bending test

4.7.6.3.1 General

Conduct the test in two stages on the same assembly as follows.

4.7.6.3.2 Requirement for stage 1

When tested by the method described in TBIS 4210-5:2016, 4.4.1, there shall be no visible cracks
or fractures and the permanent deformation measured at the point of application of the test force and
in the direction of the test force shall not exceed 10 mm and record the ratio between weight and
rigidity in the test result.

4.7.6.3.3 Requirement for stage 2

When tested by the method described in TBIS 4210-5:2016, 4.4.2, there shall be no visible cracks
or fractures and record the ratio between weight and rigidity in the test result.
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