Page 40 - 20190101 part 6 (EN)

TBIS 4210-6:2019
Annex F
(normative)

Safety test of folding mechanism of frame

F.1 General
1. The test method of the item is applicable to all frames including folding mechanisms
defined in TBIS 4210.
2. The tightening conditions of the folding mechanisms should be finished according to the
setting values of the manufacturer, and the measurement of the opening force and the
closing force should be finished before the test.
3. It is necessary to adopt a new frame to perform the test, and use the simulated front fork
(the requirements of the front fork are as shown in Annex A of TBIS 4210-6:2017), the
gear set and the handle stems with default sizes.

F.2 Requirements:
After the test is finished according to the method specifically described in F. 2, the folding
mechanism should not be broken or have visible cracks; the opening force and the closing
force of the folding mechanism should not be lower than 90% of the suggested value of the
manufacturer, and should not be stuck; in addition, the rotation shaft of the folding
mechanisms should not be loose because a gap appearing in the shaft.

F.3 Test method:
In the test conditions, the requirements of the tangential velocity and time of the wheels,
and the jump blocks are the same with Annex A of TBIS 4210-3, the only difference is that
it is driven by the ground wheel; the weight of each of the parts of the vehicle body is as
shown in the following table:
Unit: kg

Bicycle type City bike Teenager bike Mountain bike Racing bike
Weight of both free ends 6.75
of the handlebar
Weight of the seat tube 50 40 30
of the frame
Weight of the bottom
brackets(BB) of the 30 20 50
frame

32