SIST EN ISO 4210-6:2014

SLOVENSKI STANDARD
SIST EN ISO 4210-6:2014
01-oktober-2014
1DGRPHãþD
SIST EN 14764:2006
SIST EN 14766:2006
SIST EN 14781:2006
Kolesa - Varnostne zahteve za kolesa - 6. del: Preskusne metode za okvirje in
vilice koles (ISO 4210-6:2014)
Cycles - Safety requirements for bicycles - Part 6: Frame and fork test methods (ISO
4210-6:2014)
Fahrräder - Sicherheitstechnische Anforderungen an Fahrräder - Teil 6: Prüfverfahren für
Rahmen und Gabel (ISO 4210-6:2014)
Cycles - Exigences de sécurité des bicyclettes - Partie 6: Méthodes d'essai du cadre et
de la fourche (ISO 4210-6:2014)
Ta slovenski standard je istoveten z: EN ISO 4210-6:2014
ICS:
43.150 Kolesa Cycles
SIST EN ISO 4210-6:2014 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 4210-6:2014

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SIST EN ISO 4210-6:2014

EUROPEAN STANDARD
EN ISO 4210-6

NORME EUROPÉENNE

EUROPÄISCHE NORM
July 2014
ICS 43.150 Supersedes EN 14764:2005, EN 14766:2005, EN
14781:2005
English Version
Cycles - Safety requirements for bicycles - Part 6: Frame and
fork test methods (ISO 4210-6:2014)
Cycles - Exigences de sécurité des bicyclettes - Partie 6: Fahrräder - Sicherheitstechnische Anforderungen an
Méthodes d'essai du cadre et de la fourche (ISO 4210- Fahrräder - Teil 6: Prüfverfahren für Rahmen und Gabel
6:2014) (ISO 4210-6:2014)
This European Standard was approved by CEN on 21 June 2014.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same
status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United
Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2014 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 4210-6:2014 E
worldwide for CEN national Members.

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SIST EN ISO 4210-6:2014
EN ISO 4210-6:2014 (E)
Contents Page
Foreword .3
2

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SIST EN ISO 4210-6:2014
EN ISO 4210-6:2014 (E)
Foreword
This document (EN ISO 4210-6:2014) has been prepared by Technical Committee ISO/TC 149 "Cycles" in
collaboration with Technical Committee CEN/TC 333 “Cycles” the secretariat of which is held by UNI.
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by January 2015, and conflicting national standards shall be withdrawn at
the latest by July 2015.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 14764:2005, EN 14766:2005, EN 14781:2005.
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech
Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece,
Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.
Endorsement notice
The text of ISO 4210-6:2014 has been approved by CEN as EN ISO 4210-6:2014 without any modification.

3

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SIST EN ISO 4210-6:2014

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SIST EN ISO 4210-6:2014
INTERNATIONAL ISO
STANDARD 4210-6
First edition
2014-07-01
Cycles — Safety requirements for
bicycles —
Part 6:
Frame and fork test methods
Cycles — Exigences de sécurité des bicyclettes —
Partie 6: Méthodes d’essai du cadre et de la fourche
Reference number
ISO 4210-6:2014(E)
©
ISO 2014

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SIST EN ISO 4210-6:2014
ISO 4210-6:2014(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2014
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior
written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of
the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2014 – All rights reserved

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SIST EN ISO 4210-6:2014
ISO 4210-6:2014(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Frame test methods . 1
4.1 Frame — Impact test (falling mass) . 1
4.2 Frame and front fork assembly — Impact test (falling frame) . 4
4.3 Frame — Fatigue test with pedalling forces . 6
4.4 Frame — Fatigue test with horizontal forces . 9
4.5 Frame — Fatigue test with a vertical force .10
5 Fork test methods .11
5.1 Suspension forks — Tyre-clearance test .11
5.2 Suspension forks — Tensile test .12
5.3 Front fork — Static bending test .12
5.4 Front fork — Rearward impact test .13
5.5 Front fork — Bending fatigue test and rearward impact test .16
5.6 Forks intended for use with hub or disc brakes .17
5.7 Tensile test for a non-welded fork . .19
Annex A (normative) Dummy fork characteristics .20
Annex B (normative) Fork mounting fixture .22
Annex C (informative) Suspension frames — Tyre-clearance test .24
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SIST EN ISO 4210-6:2014
ISO 4210-6:2014(E)

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adherence to the WTO principles in the Technical Barriers
to Trade (TBT) see the following URL: Foreword - Supplementary information
The committee responsible for this document is ISO/TC 149, Cycles, Subcommittee SC 1, Cycles and major
sub-assemblies.
This first edition of ISO 4210-6, together with ISO 4210-1, ISO 4210-2, ISO 4210-3, ISO 4210-4, ISO 4210-5,
ISO 4210-7, ISO 4210-8, and ISO 4210-9, cancels and replaces ISO 4210:1996, which has been technically
revised.
ISO 4210 consists of the following parts, under the general title Cycles — Safety requirements for bicycles:
— Part 1: Terms and definitions
— Part 2: Requirements for city and trekking, young adult, mountain and racing bicycles
— Part 3: Common test methods
— Part 4: Braking test methods
— Part 5: Steering test methods
— Part 6: Frame and fork test methods
— Part 7: Wheels and rims test methods
— Part 8: Pedals and drive system test methods
— Part 9: Saddles and seat-post test methods
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SIST EN ISO 4210-6:2014
ISO 4210-6:2014(E)

Introduction
This International Standard has been developed in response to demand throughout the world, and the
aim has been to ensure that bicycles manufactured in compliance with this International Standard
will be as safe as is practically possible. The tests have been designed to ensure the strength and
durability of individual parts as well as of the bicycle as a whole, demanding high quality throughout
and consideration of safety aspects from the design stage onwards.
The scope has been limited to safety considerations, and has specifically avoided standardization of
components.
If the bicycle is to be used on public roads, national regulations apply.
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SIST EN ISO 4210-6:2014

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SIST EN ISO 4210-6:2014
INTERNATIONAL STANDARD ISO 4210-6:2014(E)
Cycles — Safety requirements for bicycles —
Part 6:
Frame and fork test methods
1 Scope
This part of ISO 4210 specifies the frame and fork test methods for ISO 4210-2.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO 4210-1, Cycles — Safety requirements for bicycles — Part 1: Terms and definitions
ISO 4210-2:2014, Cycles — Safety requirements for bicycles — Part 2: Requirements for city and trekking,
young adult, mountain and racing bicycles
ISO 4210-3:2014, Cycles — Safety requirements for bicycles — Part 3: Common test methods
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 4210-1 apply.
4 Frame test methods
4.1 Frame — Impact test (falling mass)
4.1.1 General
Manufacturers of frames are permitted to conduct the test with a dummy fork (see Annex A) fitted in
place of a front fork.
Where a frame is convertible for male and female riders by the removal of a bar, test it with the bar
removed.
Where a suspension fork is fitted, test the assembly with the fork extended to its unloaded free length.
Where a rear suspension system is incorporated in the frame, secure the suspension in a position
equivalent to that which would occur with an 80 kg rider seated on the bicycle. For young adult bicycles,
secure the suspension in a position equivalent to that which would occur with a 40 kg rider seated on the
bicycle; if the type of suspension system does not permit it to be locked, then replace the spring/damper
unit by a solid link of the appropriate size and with end fittings similar to those of the spring/damper
unit.
4.1.2 Test method
Assemble a roller of mass less than or equal to 1 kg and with dimensions conforming to those shown in
Figure 1 in the fork. The hardness of roller shall be not less than 60 HRC at impact surface. If a dummy
fork is used in place of a fork, the bar shall have a rounded end equivalent in shape to the roller. Hold the
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SIST EN ISO 4210-6:2014
ISO 4210-6:2014(E)

frame-fork or frame-bar assembly vertically with clamping to a rigid fixture by the rear-axle attachment
points as shown in Figure 1.
Rest a striker of mass 22,5 kg on the roller in the fork dropouts or on the rounded end of the dummy fork
and measure the wheelbase. Raise the striker to a height of h above the low-mass roller and release it
1
to strike the roller or the steel bar at a point in line with the wheel centres and against the direction of
the fork rake or rake of the bar. The drop heights are given in Table 1. The striker will bounce and this is
normal. When the striker has come to rest on the roller or dummy fork, measure the wheelbase again.
If the fork fails, the frame shall be tested with a dummy fork.
NOTE See ISO 4210-3:2014, Annex B.
Table 1 — Drop heights
Dimensions in millimetres
City and trekking Young adult
Bicycle type Mountain bicycles Racing bicycles
bicycles bicycles
Drop height, h 180 180 360 212
1
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SIST EN ISO 4210-6:2014
ISO 4210-6:2014(E)

Dimensions in millimetres
Key
h drop height
1
1 wheelbase
2 permanent deformation
3 22,5 kg striker
4 low-mass roller (1 kg max.)
5 rigid mounting for rear-axle attachment point
6 direction of rearward impact
Figure 1 — Frame and front fork assembly — Impact test (falling mass)
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SIST EN ISO 4210-6:2014
ISO 4210-6:2014(E)

4.2 Frame and front fork assembly — Impact test (falling frame)
4.2.1 General
Manufacturers of complete bicycles shall conduct the test with the frame fitted with the appropriate
front fork.
For manufacturers of frames, where the fork intended for the frame is not available, the test can be
conducted with the frame fitted with a fork which meets the requirements of the fork impact test as
described in ISO 4210-2:2014, 4.9.5.
Where a frame is convertible for male and female riders by the removal of a bar, test it with the bar
removed.
Where a suspension fork is fitted, it shall be at its unloaded length prior to the impact. If the spring/damper
unit can be locked, it shall be locked in its unloaded length position. If the spring/damper cannot be
locked, use one of the two following alternative procedures:
— secure the fork at its extended length by an external locking method, or
— replace the fork by a rigid fork which is known to meet the requirements of the impact test described
in ISO 4210-2:2014, 4.9.5 and of a length which is consistent with an 80 kg (in case of young adult
bicycles, apply 40 kg) rider seated in a normal riding position on the bicycle when it is equipped
with the suspension fork.
Where a rear suspension system is incorporated in the frame, secure the spring/damper unit in a
position equivalent to that which would occur with an 80 kg (in case of young adult bicycles, apply
40 kg) rider seated on the bicycle; if the type of suspension system does not permit it to be locked, then
replace the spring/damper unit by a solid link of the appropriate size and with end fittings similar to
those of the spring/damper unit.
4.2.2 Test method
Conduct the test on the assembly used for the test in ISO 4210-2:2014, 4.8.2 or, in the case of a frame
manufacturer who does not make forks, with the same frame with a suitable fork fitted (see 4.2.1).
As shown in Figure 2, mount the frame-fork assembly at its rear axle attachment points so that it is free
to rotate about the rear axle in a vertical plane. Support the front fork on a flat steel anvil so that the
to the seat-post as shown in Figure 2 with
frame is in its normal position of use. Securely fix mass M
1
the centre of gravity at distance D (= 75 mm) along the seat-post axis from the insertion point, and fix
masses of M and M (Table 2) to the top of the steering head and the bottom bracket, respectively, as
2 3
shown in Figure 2.
Measure the wheelbase with the three masses in place. Rotate the assembly about the rear axle until the
distance between the low-mass roller and the anvil is h , then allow the assembly to fall freely to impact
2
on the anvil.
Repeat the test and then measure the wheelbase again with the three masses in place and the roller
resting on the anvil.
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SIST EN ISO 4210-6:2014
ISO 4210-6:2014(E)

Table 2 — Drop heights and distribution of masses at seat post, steering head, and bottom
bracket
City and trekking Young adult bicy-
Bicycle type Mountain bicycles Racing bicycles
bicycles cles
Mass 1
Seat-post, M 50 40 30 30
1
kg
Mass 2
Steering head, M 10 10 10 10
2
kg
Mass 3
Bottom bracket, M 30 20 50 50
3
kg
Drop height, h
2
200 200 300 200
mm
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SIST EN ISO 4210-6:2014
ISO 4210-6:2014(E)

Dimensions in millimetres
Key
1 wheelbase
2 permanent deformation
3 mass 1 (M )
1
4 mass 2 (M )
2
5 mass 3 (M )
3
6 rigid mounting for rear-axle attachment point
7 steel anvil
D distance to the centre of gravity (75 mm)
h drop height
2
Figure 2 — Frame and front fork assembly — Impact test (falling frame)
4.3 Frame — Fatigue test with pedalling forces
4.3.1 General
All types of frame shall be subjected to this test.
In tests on suspension frames with pivoted joints, adjust the spring, air pressure, or damper to provide
maximum resistance, or, for a pneumatic damper in which the air pressure cannot be adjusted, replace
the suspension unit with a rigid link, ensuring that its end fixings and lateral rigidity accurately simulate
those of the original unit. For suspension frames in which the chain stays do not have pivots but rely on
flexing, ensure that any dampers are set to provide the minimum resistance in order to ensure adequate
testing of the frame.
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SIST EN ISO 4210-6:2014
ISO 4210-6:2014(E)

Where a suspension frame has adjustable brackets or linkages to vary the resistance of the bicycle
against the ground-contact forces or to vary the attitude of the bicycle, arrange the positions of these
adjustable components to ensure maximum forces in the frame.
4.3.2 Test method
Use a new frame/fork assembly fitted with standard head tube bearings for the test. The front fork can
be replaced by a dummy fork (see Annex A) of the same length and at least the same stiffness as the
original fork.
NOTE If a genuine fork is used, failures of the fork are possible; therefore, it is recommended that for
convenience, a dummy fork stiffer and stronger than the genuine fork be used.
Where a frame is convertible for male and female riders by the removal of a bar, test it with the bar
removed.
Mount the frame assembly on a base as shown in Figure 3 with the fork or dummy fork secured by its
(the radius of the wheel/tyre assembly ±30 mm) and with the hub free
axle to a rigid mount of height R
w
to swivel on the axle. Secure the rear dropouts by means of the axle to a stiff, vertical link of the same
height as that of the front, rigid mount, the upper connection of the link being free to swivel about the
axis of the axle but providing rigidity in a lateral plane, and the lower end of the link being fitted with a
ball-joint.
Fit a crank, chain wheel and chain assembly or, preferably, a strong, stiff, replacement assembly to the
bottom bracket as shown in Figure 3 and described in item a) or b) below.
a) If a crank/chain-wheel assembly is used, incline both cranks forwards and downwards at an angle
of 45° (accurate to within ±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 3), 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 to within ±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 (R ) shall be 75 mm and the
c
axis of the tie rod shall be parallel to and 50 mm from the vertical plane through the centreline of
the frame.
Subject each pedal spindle (or equivalent adaptor component) to a repeated downward force of F at
1
a position 150 mm from the centreline 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 3 and Figure 3. 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 ISO 4210-3:2014,
4.5.
Table 3 — Forces on pedal spindle
Forces in newtons
City and trekking
Bicycle type Young adult bicycles Mountain bicycles Racing bicycles
bicycles
Force, F 1 000 1 000 1 200 1 100
1
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SIST EN ISO 4210-6:2014
ISO 4210-6:2014(E)

Dimensions in millimetres
4
Key
R height of rigid mount and vertical link
w
R length of vertical arm (75 mm)
c
L length of crank replacement (175 mm)
1 rigid mount
2 vertical link
3 ball joint
4 adaptor assembly
5 vertical arm
6 tie rod
7 centreline of tie rod
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SIST EN ISO 4210-6:2014
ISO 4210-6:2014(E)

Figure 3 — Frame — Fatigue test with pedalling forces
4.4 Frame — Fatigue test with horizontal forces
4.4.1 General
Where a frame is convertible for male and female riders by the removal of a bar, remove the bar.
It is not necessary for a genuine fork to be fitted, provided that any substitute fork is of the same length
as the intended fork (see Annex A) and it is correctly installed in the steering-head bearings. For a
suspension fork, lock it at a length equivalent to that with an 80 kg (in case of young adult bicycles, apply
40 kg) rider seated on the bicycle either by adjusting the spring/damper or by external means.
In tests on suspension frames with pivoted joints, lock the moving part of the frame into a position as
would occur with an 80 kg rider seated on the bicycle. This can be achieved by locking the suspension
unit in an appropriate position or, if the type of suspension system does not permit it to be locked, then
the suspension system can be replaced by a solid link of the appropriate compressed size. Ensure that
the axes of the front and rear axles are horizontally in line, as shown in Figure 4. For suspension frames
in which the chain stays do not have pivots but rely on flexing, ensure that any dampers are set to
provide the minimum resistance in order to ensure adequate testing of the frame.
Where a suspension frame has adjustable brackets or linkages to vary the resistance of the bicycle
against the ground-contact forces or to vary the attitude of the bicycle, arrange the positions of these
adjustable components to ensure maximum forces in the frame.
4.4.2 Test method
Mount the frame in its normal attitude and secured at the rear dropouts so that it is not restrained in a
rotary sense (i.e. preferably by the rear axle) as shown in Figure 4. Ensure that the axis of the front and
rear axles are horizontally in line.
Apply cycles of dynamic, horizontal forces of F in a forward direction and F in a rearward direction to
2 3
the front fork dropouts for C cycles as shown in Table 4 and Figure 4, with the front fork constrained
1
in vertical direction but free to move in a fore/aft direction under the applied forces. The maximum test
frequency shall be maintained as specified in ISO 4210-3:2014, 4.5.
Table 4 — Forces and cycles on front fork dropouts
City and trekking Young adult
Bicycle type Mountain bicycles Racing bicycles
bicycles bicycles
Forward force, F
2
450 450 1 200 600
N
Rearward force, F
3
450 450 600 600
N
Test cycles, C 100 000 100 000 50 000 100 000
1
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SIST EN ISO 4210-6:2014
ISO 4210-6:2014(E)

Key
1 free-running guided roller
2 rigid, pivoted mounting for rear-axle attachment point
Figure 4 — Frame — Fatigue test with horizontal forces
4.5 Frame — Fatigue test with a vertical force
4.5.1 General
Where a frame is convertible for male and female riders by the removal of a bar, remove the bar.
Where a suspension frame has adjustable brackets or linkages to vary the resistance of the bicycle
against the ground-contact forces or to vary the attitude of the bicycle, arrange the positions of these
adjustable components to ensure maximum forces in the frame. Secure the rear suspension as described
in 4.3.1.
If a suspension fork is fitted lock it at a length equivalent to that with an 80 kg (in
...