Cycles - Safety requirements for bicycles - Part 4: Braking test methods (ISO 4210-4:2023)

This document specifies the braking test methods for ISO 4210‑2.

Fahrräder - Sicherheitstechnische Anforderungen an Fahrräder - Teil 4: Prüfverfahren für Bremsen (ISO 4210-4:2023)

Der vorliegende Teil von ISO 4210 legt die Prüfverfahren für Bremsen nach ISO 4210 2 fest.

Cycles - Exigences de sécurité pour les bicyclettes - Partie 4: Méthodes d'essai de freinage (ISO 4210-4:2023)

Kolesa - Varnostne zahteve za kolesa - 4. del: Preskusne metode za zavore (ISO 4210-4:2023)

Ta dokument določa preskusne metode za zavore za standard ISO 4210-2.

General Information

Status
Published
Public Enquiry End Date
19-Jan-2022
Publication Date
14-Mar-2023
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
02-Mar-2023
Due Date
07-May-2023
Completion Date
15-Mar-2023

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Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 4210-4:2023
01-april-2023
Nadomešča:
SIST EN ISO 4210-4:2014
Kolesa - Varnostne zahteve za kolesa - 4. del: Preskusne metode za zavore (ISO
4210-4:2023)
Cycles - Safety requirements for bicycles - Part 4: Braking test methods (ISO 4210-
4:2023)
Fahrräder - Sicherheitstechnische Anforderungen an Fahrräder - Teil 4: Prüfverfahren
für Bremsen (ISO 4210-4:2023)
Cycles - Exigences de sécurité pour les bicyclettes - Partie 4: Méthodes d'essai de
freinage (ISO 4210-4:2023)
Ta slovenski standard je istoveten z: EN ISO 4210-4:2023
ICS:
43.150 Kolesa Cycles
SIST EN ISO 4210-4:2023 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 4210-4:2023

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SIST EN ISO 4210-4:2023


EN ISO 4210-4
EUROPEAN STANDARD

NORME EUROPÉENNE

January 2023
EUROPÄISCHE NORM
ICS 43.150 Supersedes EN ISO 4210-4:2014
English Version

Cycles - Safety requirements for bicycles - Part 4: Braking
test methods (ISO 4210-4:2023)
Cycles - Exigences de sécurité pour les bicyclettes - Fahrräder - Sicherheitstechnische Anforderungen an
Partie 4: Méthodes d'essai de freinage (ISO 4210- Fahrräder - Teil 4: Prüfverfahren für Bremsen (ISO
4:2023) 4210-4:2023)
This European Standard was approved by CEN on 13 January 2023.

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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 4210-4:2023 E
worldwide for CEN national Members.

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SIST EN ISO 4210-4:2023
EN ISO 4210-4:2023 (E)
Contents Page
European foreword . 3

2

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SIST EN ISO 4210-4:2023
EN ISO 4210-4:2023 (E)
European foreword
This document (EN ISO 4210-4:2023) 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 July 2023, and conflicting national standards shall be
withdrawn at the latest by July 2023.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 4210-4:2014.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
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, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 4210-4:2023 has been approved by CEN as EN ISO 4210-4:2023 without any
modification.

3

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SIST EN ISO 4210-4:2023

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SIST EN ISO 4210-4:2023
INTERNATIONAL ISO
STANDARD 4210-4
Second edition
2023-01
Cycles — Safety requirements for
bicycles —
Part 4:
Braking test methods
Cycles — Exigences de sécurité pour les bicyclettes —
Partie 4: Méthodes d'essai de freinage
Reference number
ISO 4210-4:2023(E)
© ISO 2023

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SIST EN ISO 4210-4:2023
ISO 4210-4:2023(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2023
All rights reserved. Unless otherwise specified, or required in the context of its implementation, 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
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
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SIST EN ISO 4210-4:2023
ISO 4210-4:2023(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Test methods . 1
4.1 Brake lever grip dimensions . 1
4.1.1 Test method for the brake lever similar to type A or type B . 1
4.1.2 Test method for the brake lever similar to type C . 3
4.2 Brake levers — Position of applied force . 5
4.2.1 Type A and B brake levers . 5
4.2.2 Type C brake levers . 5
4.3 Brake-block and brake-pad assemblies — Security test . 6
4.4 Hand-operated braking-system — Strength test . 6
4.5 Back-pedal braking system — Strength test . 7
4.6 Braking performance . 7
4.6.1 Test bicycle . 7
4.6.2 Secondary brake levers . 7
4.6.3 Track test method . 8
4.6.4 Back-pedal brake linearity test . 17
4.6.5 Machine test method . 17
4.7 Brakes — Heat-resistance test .23
4.7.1 Drag test .23
4.7.2 Brake performance measurement after drag test . . 24
Annex A (informative) Explanation of the method of least squares for obtaining the line of
best fit and ±20 % limit lines for braking performance linearity .26
Annex B (informative) Method of measuring braking distance with different lever forces .29
Annex C (informative) How to derive the total braking energy for brake heat resistance test .31
iii
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SIST EN ISO 4210-4:2023
ISO 4210-4:2023(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 of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 149, Cycles, Subcommittee SC 1, Cycles
and major sub-assemblies, in collaboration with the European Committee for Standardization (CEN)
Technical Committee CEN/TC 333, Cycles, in accordance with the Agreement on technical cooperation
between ISO and CEN (Vienna Agreement).
This second edition cancels and replaces the first edition (ISO 4210-4:2014), which has been technically
revised.
The main changes are as follows:
— improvement of 4.1.2;
— addition of test temperature requirement in 4.6.3 and 4.6.5;
— change in the method of calculating the braking distance in 4.6.3;
— addition of rolling resistance requirement and cooling requirement in 4.6.5.7;
— change in the test method to no cooling air of 4.7;
— addition of Annex B and Annex C.
A list of all parts in the ISO 4210 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
iv
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SIST EN ISO 4210-4:2023
ISO 4210-4:2023(E)
Introduction
This document has been developed in response to the demand throughout the world. The aim is to
ensure that bicycles manufactured in conformity with this document will be as safe as is practically
possible. The tests are 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 is limited to safety considerations and has specifically avoided standardization of
components.
If the bicycle should be used on public roads, national regulations apply.
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SIST EN ISO 4210-4:2023

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SIST EN ISO 4210-4:2023
INTERNATIONAL STANDARD ISO 4210-4:2023(E)
Cycles — Safety requirements for bicycles —
Part 4:
Braking test methods
1 Scope
This document specifies the braking test methods for ISO 4210-2.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. 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: Vocabulary
ISO 4210-2:2023, Cycles — Safety requirements for bicycles — Part 2: Requirements for city and trekking,
young adult, mountain and racing bicycles
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 4210-1 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
4 Test methods
4.1 Brake lever grip dimensions
4.1.1 Test method for the brake lever similar to type A or type B
Fit the gauge illustrated in Figure 1 over the handlebar grip or the handlebar (when the manufacturer
does not fit a grip) and the brake lever as shown in Figure 2 so that face A is in contact with the handlebar
or grip and the side of the brake lever. Ensure that face B spans an area of that part of the brake lever
which is intended for contact with the rider's fingers without the gauge causing any movement of the
brake lever towards the handlebar or grip. Measure the distance, a, the distance between the last part
of the lever intended for contact with the rider's fingers and the end of the lever. The measurement
should be conducted only on a fully assembled bicycle.
1
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SIST EN ISO 4210-4:2023
ISO 4210-4:2023(E)
Dimensions in millimetres
Key
A face A
B face B
C rod
D 75 mm or 90 mm
Figure 1 — Brake lever grip dimension gauge for type A and type B
a) Type A
2
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SIST EN ISO 4210-4:2023
ISO 4210-4:2023(E)
b) Type B
Key
a distance between the last part of the lever intended for contact with the rider's fingers and the end of the lever
Figure 2 — Method of fitting the gauge to the brake lever and handlebar
4.1.2 Test method for the brake lever similar to type C
Fit the gauge illustrated in Figure 3 over the handlebar and brake lever as shown in Figure 4 so that face
A is in contact with the handlebar or handlebar grip and the brake lever. Put the face of cylinder B in
contact with the part of the grip intended for contact with the rider’s hand and check if the requirements
are met. In the case of brake lever with position adjustment, check if the requirements are met in a
specific range of the adjustable range.
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SIST EN ISO 4210-4:2023
ISO 4210-4:2023(E)
Dimensions in millimetres
Key
A face A
B face of cylinder
C rod
Figure 3 — Brake lever grip-dimension gauge for type C
Figure 4 — Method of fitting the gauge to the brake lever and handlebar for type C
4
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SIST EN ISO 4210-4:2023
ISO 4210-4:2023(E)
4.2 Brake levers — Position of applied force
4.2.1 Type A and B brake levers
For the purposes of braking tests in this document, for brake levers similar to type A or type B, the
test force shall be applied at a distance b, which is equal to either dimension a [see ISO 4210-2:2023,
Figure 1 a) and b)] as determined in 4.1.1 or 25 mm from the free end of the brake lever, whichever is
the greater [see Figure 5 a) and Figure 5 b)].
4.2.2 Type C brake levers
For the purposes of braking tests in this document, for brake levers similar to type C, the test force shall
be applied at a distance of 25 mm from the free end of the brake lever [see Figure 5 c)].
Dimensions in millimetres
a)  Type A b)  Type B

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SIST EN ISO 4210-4:2023
ISO 4210-4:2023(E)
c)  Type C
Key
F applied force
b ≥25 mm
Figure 5 — Position of applied force on the brake lever
4.3 Brake-block and brake-pad assemblies — Security test
Conduct the test on a fully assembled bicycle with the brakes adjusted to a correct position with a rider
or equivalent mass on the saddle. The combined mass of the bicycle and rider (or equivalent mass) shall
be 100 kg.
Actuate each brake lever with a force of 180 N applied at the point specified in Figure 5 or a force
sufficient to bring the brake lever into contact with the handlebar grip, whichever is lesser. Maintain
this force while subjecting the bicycle to five forward and five rearward movements, each of which is
not less than 75 mm distance.
Then conduct the test described in 4.4 or 4.5 as appropriate, depending on the style of brake, and then
the test described in 4.6.
4.4 Hand-operated braking-system — Strength test
Conduct the test on a fully assembled bicycle. After it has been ensured that the braking system is
adjusted according to the recommendations in the manufacturer's instructions, apply a force to the
brake lever at the point specified in Figure 5. This force shall be 450 N, or such lesser force as is required
to bring
a) a brake lever into contact with the handlebar grip or the handlebar where the manufacturer does
not fit a grip,
b) a brake extension lever level with the surface of the handlebar or in contact with the handlebar,
and
c) a secondary brake lever to the end of its travel.
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SIST EN ISO 4210-4:2023
ISO 4210-4:2023(E)
Repeat the test 10 times on each brake lever, secondary brake lever, or extension lever.
4.5 Back-pedal braking system — Strength test
Conduct the test on a fully assembled bicycle. After it has been ensured that the braking system is
correctly adjusted, and with the pedal cranks in a horizontal position, as shown in Figure 6, apply a
vertically downward force to the centre of the left-hand pedal spindle. Increase the force progressively
to 1 500 N and maintain fully for 1 min.
Key
1 chain
2 hub sprocket
3 non-drive side crank
4 chain wheel and pedal crank
5 point of force application
6 pedal
F vertically downward force to the centre of the left-hand pedal spindle, 1 500 N
Figure 6 — Back-pedal brake test
4.6 Braking performance
4.6.1 Test bicycle
Conduct the braking performance test on a fully assembled bicycle after the brakes have been
subjected to the strength test detailed in ISO 4210-2:2023, 4.6.6, and 4.6.7. Before testing the bicycle
by either method, inflate the tyres and adjust the brakes to the nominal reach position according to the
manufacturer's instructions. In the case of rim-brakes, adjust it to the maximum clearance specified by
the manufacturer.
4.6.2 Secondary brake levers
Where a bicycle is fitted with secondary brake levers attached to brake levers, bar-ends, or aerodynamic
extensions, separate tests shall be conducted for the operation of the secondary brake levers in addition
to tests with the normal levers.
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SIST EN ISO 4210-4:2023
ISO 4210-4:2023(E)
4.6.3 Track test method
4.6.3.1 Test track
a) Use an indoor test track if possible. If an outdoor test track is used, pay special attention to ambient
conditions throughout the test. The ambient temperature while performing the test shall be
20 °C ±10 °C.
b) The gradient of the track shall not exceed 0,5 %. If the gradient is less than 0,2 % carry out all runs
in the same direction. If the gradient lies between 0,2 % and 0,5 %, carry out alternate runs in
opposite directions.
c) The surface shall be hard, of concrete or fine asphalt, and free from loose dirt or gravel. The
minimum coefficient of friction between the dry surface and the bicycle tyre shall be 0,75.
d) The track shall be essentially dry at the commencement of tests. When testing in accordance with
the requirements of 4.6.3.6, the track shall remain dry throughout the tests.
e) The wind speed on the track shall not exceed 3 m/s during the tests.
4.6.3.2 Instrumentation
The test bicycle or the test track shall be instrumented to include the following:
a) a calibrated speedometer or tachometer (accurate to within ±5 %) to indicate to the rider the
approximate speed at the commencement of braking;
b) a velocity-recording device (accurate to within ±2 %) to record the velocity at the commencement
of braking;
c) a distance recording system (accurate to within ±1 %) to record the braking distance;
The velocity-recording device and distance recording system should have the least possible resistance
to the road surface.
d) a water spray system, to provide wetting of the braking surface, consisting of a water reservoir
connected by tubing to a pair of nozzles at the front wheel and a pair of nozzles at the rear wheel.
A quick-acting on/off valve shall be included for control by the rider. Each nozzle shall provide a
flow of water at ambient temperature of not less than 4 ml/s. Details of the positions and directions
of nozzles for rim brakes, hub brakes, band brakes, disc brakes, and back-pedal brake are given in
Figures 7 to 13;
NOTE Figures 7 and 8 for rim brakes show side-pull callipers but the same arrangements apply to
centre-pull callipers and cantilever brakes.
e) a brake-actuation indicating system to record independently when each lever or pedal is actuated.
4.6.3.3 Mass of bicycle, rider, and instrumentation
The combined mass of the bicycle, the rider, and the instrumentation shall be 100 kg.
When wet condition braking tests are performed, the combined mass can decrease throughout the test
due to water consumption, but it shall not be less than 99 kg at the end of the valid test runs.
Where a manufacturer specifies that their bicycle can carry a mass such that the sum of that mass plus
the mass of the bicycle is in excess of 100 kg (60 kg for young adults) to some value M, apply M as total
mass.
Any extra mass shall be positioned above the rear wheel and in front of the rear axle.
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SIST EN ISO 4210-4:2023
ISO 4210-4:2023(E)
4.6.3.4 Force applied to the brake levers
a) Magnitude and position of force on brake levers
Apply a handgrip force not exceeding 180 N at the point as specified in Figure 5. Check before and
after each series of test runs to verify the lever force. In order to stabilize the lever operating force
during braking, the lever may be fitted with an attachment which limits its range of movement. Brakes
that produce high braking forces with small operating forces should have their brake characteristics
checked beforehand to ensure that they can be tested safely.
NOTE When the braking distance can only be measured at lower lever operating force, see Annex B for the
calculation of the braking distance at a maximum lever operating force (bottom up or 180 N).
b) Optional brake-force application device
It is permissible to use a test mechanism to operate the brake lever, and when such a device is used, it
shall meet the requirements of 4.6.3.4 item a) and shall additionally control the rate of application of
the brake lever force such that 63 % of the intended lever force is applied in not less than 0,2 s.
4.6.3.5 Running — in the braking surfaces
A running-in process shall be conducted on every brake before performance testing is carried out.
Apply the brakes for not less than 3 s to maintain steady deceleration while the bicycle is being ridden
at a speed of approximately 16 km/h. Repeat this operation 10 times.
4.6.3.6 Test method — Test runs under dry conditions
Pedal the test bicycle until the specified test velocity is attained (see ISO 4210-2:2023, Table 1).
Then stop pedalling and apply the brakes. The bicycle shall be brought to a smooth, safe stop [see
ISO 4210-2:2023, 4.6.8.2 item a)].
4.6.3.7 Test method — Test runs under wet conditions
The method shall be as given in 4.6.3.6, with the addition that wetting of the brake system(s) shall
commence not less than 25 m prior to the commencement of braking and shall continue until the bicycle
comes to rest. Excessive amounts of water can be swept from the test track surface between runs.
4.6.3.8 Number of valid test runs
a) If the gradient of the track is less than 0,2 %, the following runs shall be made:
1) five consecutive valid runs under dry conditions;
2) two acclimatization runs under wet conditions (results not recorded);
3) five consecutive valid runs under wet conditions.
b) If the gradient of the track lies between 0,2 % and 0,5 %, the following runs shall be made:
1) six consecutive valid runs under dry conditions with alternate runs in opposite directions;
2) two acclimatization runs under wet conditions (results not recorded);
3) six consecutive valid runs under wet conditions with alternate runs in opposite directions.
A rest period not exceeding 3 min can be taken between successive runs.
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SIST EN ISO 4210-4:2023
ISO 4210-4:2023(E)
Key
1 water nozzles
2 fork crown
3 front tee-piece
4 wheel rim
a
Direction of the wheel rotation.
Figure 7 — Water nozzles for rim-brake (front)
10
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SIST EN ISO 4210-4:2023
ISO 4210-4:2023(E)
Dimensions in millimetres
Key
1 water nozzles
2 rear tee-piece
3 bicycle frame
4 wheel rim
5 brake assembly
a
Direction of the wheel rotation.
Figure 8 — Water nozzles for rim-brake (rear)
Key
1 water nozzle
2 two water nozzles
3 hub brake
a
Direction of the wheel rotation.
Figure 9 — Water nozzles for hub-brake
11
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SIST EN ISO 4210-4:2023
ISO 4210-4:2023(E)
Dimensions in millimetres
Key
1 water nozzle
2 bicycle frame
3 rear tee-piece
4 band brake
5 rear hub
a
Direction of the wheel rotation.
Figure 10 — Water nozzles for band-brake
12
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SIST EN ISO 4210-4:2023
ISO 4210-4:2023(E)
Dimensions in millimetres
Key
1 front hub
2 water nozzles
3 flexible pipe
4 suspension-fork leg
5 Y-joint
6 brake-disc
7 disc-brake calliper
a
Direction of the wheel rotation.
Figure 11 — Water nozzles for disc-brake (front)
13
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SIST EN
...

SLOVENSKI STANDARD
oSIST prEN ISO 4210-4:2022
01-januar-2022
Kolesa - Varnostne zahteve za kolesa - 4. del: Preskusne metode za zavore
(ISO/DIS 4210-4:2021)
Cycles - Safety requirements for bicycles - Part 4: Braking test methods (ISO/DIS 4210-
4:2021)
Fahrräder - Sicherheitstechnische Anforderungen an Fahrräder - Teil 4: Prüfverfahren
für Bremsen (ISO/DIS 4210-4:2021)
Cycles - Exigences de sécurité des bicyclettes - Partie 4 : Méthodes d'essai de freinage
(ISO/DIS 4210-4:2021)
Ta slovenski standard je istoveten z: prEN ISO 4210-4
ICS:
43.150 Kolesa Cycles
oSIST prEN ISO 4210-4:2022 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 4210-4:2022

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oSIST prEN ISO 4210-4:2022
DRAFT INTERNATIONAL STANDARD
ISO/DIS 4210-4
ISO/TC 149/SC 1 Secretariat: JISC
Voting begins on: Voting terminates on:
2021-11-05 2022-01-28
Cycles — Safety requirements for bicycles —
Part 4:
Braking test methods
Cycles — Exigences de sécurité des bicyclettes —
Partie 4: Méthodes d'essai de freinage
ICS: 43.150
THIS DOCUMENT IS A DRAFT CIRCULATED
This document is circulated as received from the committee secretariat.
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
ISO/CEN PARALLEL PROCESSING
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 4210-4:2021(E)
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
©
PROVIDE SUPPORTING DOCUMENTATION. ISO 2021

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oSIST prEN ISO 4210-4:2022
ISO/DIS 4210-4:2021(E)
ISO/DIS 4210-4:2021(E)

Contents
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to maintain the Table of Contents automatically and apply auto-numbering.
To update the Table of Contents please select it and press "F9".
Foreword . iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Test methods . 1
4.1 Brake lever grip dimensions. 1
4.1.1 Test method for the brake lever similar to type A or type B . 1
4.1.2 Test method for the brake lever similar to type C . 3
4.2 Brake levers — Position of applied force . 5
4.2.1 Type A and B brake levers . 5
4.2.2 Type C brake levers. 5
4.3 Brake-block and brake-pad assemblies — Security test . 6
4.4 Hand-operated braking-system — Strength test. 7
4.5 Back-pedal braking system — Strength test . 7
4.6 Braking performance . 8
4.6.1 Test bicycle . 8
4.6.2 Secondary brake levers . 8
4.6.3 Track test method . 8
4.6.4 Back-pedal brake linearity test . 18
4.6.5 Machine test method . 19
4.7 Brakes — Heat-resistance test . 25
Annex A (informative) Explanation of the method of least squares for obtaining the line of
best fit and ±20 % limit lines for braking performance linearity . 27
Bibliography . 30

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ii © ISO 2021 – All rights reserved
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oSIST prEN ISO 4210-4:2022
ISO/DIS 4210-4:2021(E)
Contents
This template allows you to work with default MS Word functions and styles. You can use these if you want
to maintain the Table of Contents automatically and apply auto-numbering.
To update the Table of Contents please select it and press "F9".
Foreword .iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Test methods . 1
4.1 Brake lever grip dimensions . 1
4.1.1 Test method for the brake lever similar to type A or type B . 1
4.1.2 Test method for the brake lever similar to type C . 3
4.2 Brake levers — Position of applied force . 5
4.2.1 Type A and B brake levers . 5
4.2.2 Type C brake levers. 5
4.3 Brake-block and brake-pad assemblies — Security test . 6
4.4 Hand-operated braking-system — Strength test . 7
4.5 Back-pedal braking system — Strength test . 7
4.6 Braking performance . 8
4.6.1 Test bicycle . 8
4.6.2 Secondary brake levers . 8
4.6.3 Track test method . 8
4.6.4 Back-pedal brake linearity test . 18
4.6.5 Machine test method . 19
4.7 Brakes — Heat-resistance test . 25
Annex A (informative) Explanation of the method of least squares for obtaining the line of
best fit and ±20 % limit lines for braking performance linearity . 27
Bibliography . 30

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oSIST prEN ISO 4210-4:2022
ISO/DIS 4210-4:2021(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 of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the World
Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 149, Cycles, Subcommittee SC 1, Cycles and
major sub-assemblies.
This second edition cancels and replaces the first edition (ISO 4210-4:2014), which has been technically
revised.
The main changes compared to the previous edition are as follows:
— xxx xxxxxxx xxx xxxx
A list of all parts in the ISO 4210 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
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Introduction
This International Standard has been developed in response to the demand throughout the world. The
aim is to ensure that bicycles manufactured in compliance with this International Standard will be as safe
as is practically possible. The tests are 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 is 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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oSIST prEN ISO 4210-4:2022
DRAFT INTERNATIONAL STANDARD ISO/DIS 4210-4:2021(E)

1 Cycles — Safety requirements for bicycles — Part 4: Braking test
2 methods
3 1 Scope
4 This part of ISO 4210 specifies the braking test methods for ISO 4210-2.
5 2 Normative references
6 The following documents are referred to in the text in such a way that some or all of their content
7 constitutes requirements of this document. For dated references, only the edition cited applies. For
8 undated references, the latest edition of the referenced document (including any amendments) applies.
9 ISO 4210-1, Cycles — Safety requirements for bicycles — Part 1: Terms and definitions
10 ISO 4210-2, Cycles — Safety requirements for bicycles — Part 2: Requirements for city & trekking, young
11 adult, mountain and racing bicycles
12 3 Terms and definitions
13 For the purposes of this document, the terms and definitions given in ISO 4210-1 apply.
14 ISO and IEC maintain terminological databases for use in standardization at the following addresses:
15 — ISO Online browsing platform: available at https://www.iso.org/obp
16 — IEC Electropedia: available at http://www.electropedia.org/
17 4 Test methods
18 4.1 Brake lever grip dimensions
19 4.1.1 Test method for the brake lever similar to type A or type B
20 Fit the gauge illustrated in Figure 1 over the handlebar grip or the handlebar (when the manufacturer
21 does not fit a grip) and the brake lever as shown in Figure 2 so that face A is in contact with the handlebar
22 or grip and the side of the brake lever. Ensure that face B spans an area of that part of the brake lever
23 which is intended for contact with the rider's fingers without the gauge causing any movement of the
24 brake lever towards the handlebar or grip. Measure the distance, a, the distance between the last part of
25 the lever intended for contact with the rider's fingers and the end of the lever. The measurement should
26 be conducted only on a fully assembled bicycle.
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27 Dimensions in millimetres
28
29 Key
A face A
B face B
C rod
D 75 mm or 90 mm
30 Figure 1 — Brake lever grip dimension gauge for type A and type B
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a) Type A

b) Type B
31 Figure 2 — Method of fitting the gauge to the brake lever and handlebar
32 4.1.2 Test method for the brake lever similar to type C
33 Fit the gauge illustrated in Figure 3 over the handlebar and brake lever as shown in Figure 4 so that face
34 A is in contact with the handlebar or handlebar grip and the brake lever. Put the face of cylinder B in
35 contact with the part of the grip intended for contact with the rider’s hand and check if the requirements
36 are met. In the case of brake lever with position adjustment, check if the requirements are met in a specific
37 range of the adjustable range.
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38 Dimensions in millimetres
39
40 Key
A face A
B face of cylinder
C rod
41 Figure 3 — Brake lever grip-dimension gauge for type C
42
43 Figure 4 — Method of fitting the gauge to the brake lever and handlebar for type C
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44 4.2 Brake levers — Position of applied force
45 4.2.1 Type A and B brake levers
46 For the purposes of braking tests in this part of ISO 4210, for brake levers similar to type A or type B, the
47 test force shall be applied at a distance b, which is equal to either dimension a [see ISO 4210-2, Figure 2
48 a) and b)] as determined in 4.1.1 or 25 mm from the free end of the brake lever, whichever is the greater
49 [see Figure 5 a) and Figure 5 b)].
50 4.2.2 Type C brake levers
51 For the purposes of braking tests in this part of ISO 4210, for brake levers similar to type C, the test force
52 shall be applied at a distance of 25 mm from the free end of the brake lever [see Figure 5 c)].
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a) Type A b) Type B

c) Type C
53 Key
F applied force
b ≥ 25 mm
54 Figure 5 — Position of applied force on the brake lever
55 4.3 Brake-block and brake-pad assemblies — Security test
56 Conduct the test on a fully assembled bicycle with the brakes adjusted to a correct position with a rider
57 or equivalent mass on the saddle. The combined mass of the bicycle and rider (or equivalent mass) shall
58 be 100 kg.
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59 Actuate each brake lever with a force of 180 N applied at the point specified in Figure 5 or a force
60 sufficient to bring the brake lever into contact with the handlebar grip, whichever is lesser. Maintain this
61 force while subjecting the bicycle to five forward and five rearward movements, each of which is not less
62 than 75 mm distance.
63 Then conduct the test described in 4.4 or 4.5 as appropriate, depending on the style of brake, and then
64 the test described in 4.6.
65 4.4 Hand-operated braking-system — Strength test
66 Conduct the test on a fully assembled bicycle. After it has been ensured that the braking system is adjusted
67 according to the recommendations in the manufacturer's instructions, apply a force to the brake lever at
68 the point specified in Figure 5. This force shall be 450 N, or such lesser force as is required to bring
69 a) a brake lever into contact with the handlebar grip or the handlebar where the manufacturer does not
70 fit a grip,
71 b) a brake extension lever level with the surface of the handlebar or in contact with the handlebar, and
72 c) a secondary brake lever to the end of its travel.
73 Repeat the test 10 times on each brake lever, secondary brake lever, or extension lever.
74 4.5 Back-pedal braking system — Strength test
75 Conduct the test on a fully assembled bicycle. After it has been ensured that the braking system is
76 correctly adjusted, and with the pedal cranks in a horizontal position, as shown in Figure 6, apply a
77 vertically downward force to the centre of the left-hand pedal spindle. Increase the force progressively
78 to 1 500 N and maintain fully for 1 min.
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79
80 Key
1 chain
2 hub sprocket
3 non-drive side crank
4 cycle chain wheel and pedal crank
5 point of force application
6 pedal
81 Figure 6 — Back-pedal brake test
82 4.6 Braking performance
83 4.6.1 Test bicycle
84 Conduct the braking performance test on a fully assembled bicycle after the brakes have been subjected
85 to the strength test detailed in ISO 4210-2, 4.6.6, and 4.6.7. Before testing the bicycle by either method,
86 inflate the tyres and adjust the brakes to the nominal reach position according to the manufacturer's
87 instructions. In the case of rim-brakes, adjust it to the maximum clearance specified by the manufacturer.
88 4.6.2 Secondary brake levers
89 Where a bicycle is fitted with secondary brake levers attached to brake levers, bar-ends, or aerodynamic
90 extensions, separate tests shall be conducted for the operation of the secondary brake levers in addition
91 to tests with the normal levers.
92 4.6.3 Track test method
93 4.6.3.1 Test track
94 a) Use an indoor test track if possible. If an outdoor test track is used, pay special attention to ambient
95 conditions throughout the test. The ambient temperature while performing the test shall be
96 20 °C ±10 °C.
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97 b) The gradient of the track shall not exceed 0,5 %. If the gradient is less than 0,2 % carry out all runs
98 in the same direction. If the gradient lies between 0,2 % and 0,5 %, carry out alternate runs in
99 opposite directions.
100 c) The surface shall be hard, of concrete or fine asphalt, and free from loose dirt or gravel. The minimum
101 coefficient of friction between the dry surface and the bicycle tyre shall be 0,75.
102 d) The track shall be essentially dry at the commencement of tests. When testing to the requirements
103 of 4.6.3.6, the track shall remain dry throughout the tests.
104 e) The wind speed on the track shall not exceed 3 m/s during the tests.
105 4.6.3.2 Instrumentation
106 The test bicycle or the test track shall be instrumented to include the following:
107 a) a calibrated speedometer or tachometer (accurate to within ±5 %) to indicate to the rider the
108 approximate speed at the commencement of braking;
109 b) a velocity-recording device (accurate to within ±2 %) to record the velocity at the commencement of
110 braking;
111 c) a distance recording system (accurate to within ±1 %) to record the braking distance;
112 d) a water spray system, to provide wetting of the braking surface, consisting of a water reservoir
113 connected by tubing to a pair of nozzles at the front wheel and a pair of nozzles at the rear wheel. A
114 quick-acting on/off valve shall be included for control by the rider. Each nozzle shall provide a flow
115 of water at ambient temperature of not less than 4 ml/s. Details of the positions and directions of
116 nozzles for rim brakes, hub brakes, band brakes, disc brakes, and back-pedal brake are given in
117 Figures 7 to 13;
118 NOTE Figures 7 and 8 for rim brakes show side-pull callipers but the same arrangements apply to centre-pull
119 callipers and cantilever brakes.
120 e) a brake-actuation indicating system to record independently when each lever or pedal is actuated.
121 4.6.3.3 Mass of bicycle, rider, and instrumentation
122 The combined mass of the bicycle, the rider, and the instrumentation shall be 100 kg.
123 When wet condition braking tests are performed, the combined mass can decrease throughout the test
124 due to water consumption, but it shall not be less than 99 kg at the end of the valid test runs.
125 Where a manufacturer specifies that their bicycle can carry a mass such that the sum of that mass plus
126 the mass of the bicycle is in excess of 100 kg (60 kg for young adults) to some value M, apply M as total
127 weight.
128 Any extra weight shall be positioned above the rear wheel and in front of the rear axle.
129 4.6.3.4 Force applied to the brake levers
130 a) Magnitude and position of force on brake levers
131 Apply a handgrip force not exceeding 180 N at the point as specified in Figure 5. Check before and after
132 each series of test runs to verify the lever force.
133 b) Optional brake-force application device
134 It is permissible to use a test mechanism to operate the brake lever, and when such a device is used, it
135 shall meet the requirements of 4.6.3.4 item a) and shall additionally control the rate of application of the
136 brake lever force such that 63 % of the intended lever force is applied in not less than 0,2 s.
137 4.6.3.5 Running — in the braking surfaces
138 A running-in process shall be conducted on every brake before performance testing is carried out.
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139 Apply the brakes for not less than 3 s to maintain steady deceleration while the bicycle is being ridden at
140 a speed of approximately 16 km/h. Repeat this operation 10 times.
141 4.6.3.6 Test method — Test runs under dry conditions
142 Pedal the test bicycle until the specified test velocity is attained (see ISO 4210-2, Table 2). Then stop
143 pedalling and apply the brakes. The bicycle shall be brought to a smooth, safe stop [see ISO 4210-2, 4.6.8.2
144 item a)].
145 4.6.3.7 Test method — Test runs under wet conditions
146 The method shall be as given in 4.6.3.6, with the addition that wetting of the brake system(s) shall
147 commence not less than 25 m prior to the commencement of braking and shall continue until the bicycle
148 comes to rest. Excessive amounts of water can be swept from the test track surface between runs.
149 4.6.3.8 Number of valid test runs
150 a) If the gradient of the track is less than 0,2 %, the following runs shall be made:
151 1) five consecutive valid runs under dry conditions;
152 2) two acclimatization runs under wet conditions (results not recorded);
153 3) five consecutive valid runs under wet conditions.
154 b) If the gradient of the track lies between 0,2 % and 0,5 %, the following runs shall be made:
155 1) six consecutive valid runs under dry conditions with alternate runs in opposite directions;
156 2) two acclimatization runs under wet conditions (results not recorded);
157 3) six consecutive valid runs under wet conditions with alternate runs in opposite directions.
158 A rest period not exceeding 3 min can be taken between successive runs.
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159
160 Key
1 water nozzles
2 fork crown
3 front tee-piece
4 wheel rim
5 direction of the wheel rotation
161 Figure 7 — Water nozzles for rim-brake (front)
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162 Dimensions in millimetres
163
164 Key
1 water nozzles
2 rear tee-piece
3 bicycle frame
4 wheel rim
5 brake assembly
6 direction of the wheel rotation
165 Figure 8 — Water nozzles for rim-brake (rear)
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166
167 Key
1 water nozzle
2 two water nozzles
3 hub brake
4 direction of the wheel rotation
168 Figure 9 — Water nozzles for hub-brake
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169 Dimensions in millimetres
170
171 Key
1 water nozzle
2 bicycle frame
3 rear tee-piece
4 band brake
5 rear hub
6 direction of the wheel rotation
172 Figure 10 — Water nozzles for band-brake
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173 Dimensions in millimetres
174
175 Key
1 front hub
2 water nozzles
3 flexible pipe
4 suspension-fork leg
5 Y-joint
6 brake-disc
7 direction of the wheel rotation
8 disc-brake calliper
176 Figure 11 — Water nozzles for disc-brake (front)
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177 Dimensions in millimetres
178
179 Key
1 water nozzles
2 bicycle frame
3 rear hub
4 Y-joint
5 brake disc
6 disc-brake calliper
7 direction of the wheel rotation
180 Figure 12 — Water nozzles for
...

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