ISO 13988:2021

Passenger car and light truck vehicle wheels - Clip and adhesive balance weight and rim flange nomenclature, test procedures and performance requirements

This document specifies procedures and minimum performance requirements for testing without tyres the retention of balance weights for use on wheels for passenger vehicles. It also specifies general features for configurations of clip balance weights, rim flanges for light alloy and steel wheels intended for use on passenger cars and adhesive balance weights. Alternative materials and geometries can be considered in the future.

Roues pour véhicules particuliers et camionnettes — Nomenclature des masselottes d'équilibrage clippées et adhésives ainsi que des rebords de jantes, méthodes d'essai et exigences de performance

General Information

• Status: Published
• Publication Date: 26-Aug-2021
• ICS: 43.040.50 - Transmissions, suspensions
• Technical Committee: ISO/TC 22/SC 33 - Vehicle dynamics and chassis components
• Drafting Committee: ISO/TC 22/SC 33/WG 5 - Wheels
• Current Stage: 6060 - International Standard published
• Start Date: 27-Aug-2021
• Completion Date: 27-Aug-2021

Relations

• Revises: ISO 13988:2008 - Passenger vehicle wheels - Clip balance weight and rim flange nomenclature, test procedures and performance requirements
• Effective Date: 10-Dec-2016

Overview

ISO 13988:2021 specifies nomenclature, test procedures and minimum performance requirements for clip and adhesive balance weights used on passenger car and light truck wheels. The standard covers general features and key dimensions for clip weights (clips, spurs, weight gap, clip depth) and adhesive weights (weight portion and tape portion), and defines rim flange characteristics relevant to light alloy and steel wheels. Tests are carried out without tyres and evaluate balance weight retention under service-like conditions. This second edition adds adhesive weight requirements to the original clip-only standard.

Key Topics and Requirements

• Nomenclature & definitions: clear terms for balance weight assemblies, clip components, rim flange features and key dimensions (e.g., weight size in grams, retention force in newtons).
• Rim flange types: coverage of rim flange configurations (notably types J and B) and associated key flange dimensions for light alloy, rolled-formed, full-face and clad wheels.
• Clip balance weight features: dimensions and design aspects including clip height, weight gap, spur depth, contact radius and interference (press fit).
• Adhesive balance weight features: weight portion and three-layer tape construction (adhesive-back adhesive) and general installation considerations.
• Test procedures: preparation, installation and retention testing sequences for clip and adhesive weights, including:
  • Tangential force tests (clip weights)
  • Axial removal tests (clip weights)
  • Shear adhesion tests (adhesive weights)
  • Pull-off adhesion tests (adhesive weights)
• Test preparation: wheel cleaning, marking of mounting points, measurement of rim and weight key dimensions, and use of representative sets of new weights for testing.
• Performance requirements: minimum retention characteristics to demonstrate acceptable balance weight retention in service conditions (document defines how retention force and adhesion are measured).

Applications and Who Uses It

ISO 13988:2021 is intended for:

• Wheel and rim manufacturers (light alloy and steel) ensuring flange compatibility with clip or adhesive weights
• Balance weight and aftermarket part suppliers designing clip-on and adhesive solutions
• Automotive OEMs and Tier‑1 suppliers validating wheel assembly and NVH (noise, vibration, harshness) performance
• Independent testing laboratories and certification bodies performing retention and adhesion tests
• Tyre and wheel service centers / fitters seeking guidance on correct installation points and expected retention performance

Adoption of this standard improves safety and reliability by reducing lost weights, vibration issues and corrosion risks, and supports product compatibility across wheel types.

Related Standards

• ISO 3911 - Wheels and rims vocabulary, designation and marking
• ISO 4000-1 / ISO 4000-2 - Passenger car tyres and rims (tyres and rims dimensions)
• ISO 4223-1 - Tyre industry definitions

Keywords: ISO 13988:2021, clip balance weight, adhesive balance weight, rim flange, retention test, passenger car wheels, light alloy wheels, steel wheels, test procedures, performance requirements.

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 13988
Second edition
2021-08
Passenger car and light truck vehicle
wheels — Clip and adhesive balance
weight and rim flange nomenclature,
test procedures and performance
requirements
Roues pour véhicules particuliers et camionnettes — Nomenclature
des masselottes d'équilibrage clippées et adhésives ainsi que des
rebords de jantes, méthodes d'essai et exigences de performance
Reference number
©
ISO 2021
© ISO 2021
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: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2021 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Rim flange types . 6
5 Test procedure for clip on balance weight . 6
5.1 Preparation of clip on balance weight for test . 6
5.1.1 Selection of balance weights . 6
5.1.2 Measurement of key dimensions of balance weights . 6
5.1.3 Marking of balance weights . 6
5.2 Preparation of the wheel for clip on balance weight testing . 7
5.2.1 Cleaning . 7
5.2.2 Marking . 7
5.2.3 Measurement of rim flange dimensions . 7
5.3 Installation of clip on balance weight. 7
5.4 Tangential test for clip on balance weight . 8
5.4.1 General. 8
5.4.2 Test equipment . 8
5.4.3 Test sequence . . . 9
5.4.4 Performance requirements tangential force. 9
5.5 Axial removal test for clip on balance weight . 9
5.5.1 Test equipment . 9
5.5.2 Test sequence . . . 9
5.5.3 Performance requirement axial force .11
6 Test procedure for adhesive balance weights for all size weights and wheels .11
6.1 Test equipment .11
6.2 Wheel preparation .12
6.3 Balance weight selection and installation .12
7 Shear adhesion test.13
7.1 Test procedure .13
7.2 Performance .13
8 Pull-off adhesion test .13
8.1 Test procedure .13
8.2 Performance .14
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
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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
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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 22, Road vehicles, Subcommittee SC 33,
Vehicle dynamics and chassis components.
This second edition cancels and replaces the first edition (ISO 13988:2008), which has been technically
revised. The main changes compared with the previous edition are as follows:
— adhesive balance weights have been added, which covers clip on weights only;
— nomenclature for the balance weight and test procedures and performance requirements for the
adhesive weights have been included.
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 © ISO 2021 – All rights reserved

Introduction
This document addresses clip and adhesive balance weights used on passenger car wheels. It provides
general features and configurations of the clip balance weights, general features of the adhesive balance
weights, and general features and configurations for rim dimensions relevant to clip on weights and
defines terms used to describe these features.
This document provides test procedures to evaluate weight retention on the wheel.
INTERNATIONAL STANDARD ISO 13988:2021(E)
Passenger car and light truck vehicle wheels — Clip and
adhesive balance weight and rim flange nomenclature, test
procedures and performance requirements
1 Scope
This document specifies procedures and minimum performance requirements for testing without
tyres the retention of balance weights for use on wheels for passenger vehicles. It also specifies general
features for configurations of clip balance weights, rim flanges for light alloy and steel wheels intended
for use on passenger cars and adhesive balance weights. Alternative materials and geometries can be
considered in the future.
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 3911, Wheels and rims for pneumatic tyres — Vocabulary, designation and marking
ISO 4000-1, Passenger car tyres and rims — Part 1: Tyres (metric series)
ISO 4000-2, Passenger car tyres and rims — Part 2: Rims
ISO 4223-1, Definitions of some terms used in the tyre industry — Part 1: Pneumatic tyres
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 3911, ISO 4000-1, ISO 4000-2,
ISO 4223-1 and the following 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/
3.1
clip balance weight assembly
assembly of the weight (3.1.1) and the clip (3.1.3), which is intended for mounting on the rim flange (3.3)
to balance the tyre/wheel assembly about its axis of rotation and thus minimize vibrations due to the
rotation of the tyre/wheel assembly
Note 1 to entry: Figure 1 gives the terminology and nomenclature of balance weight assembly.
Key
1 clip 7 outer surface of clip 13 weight gap
2 spur 8 balance weight 14 clip insertion point
3 clip depth 9 contact radius 15 back leg of clip
4 spur location 10 front surface 16 clip gap
5 spur depth 11 bottom surface 17 weight depth
6 clip height 12 top surface 18 compound radius
19 compound radius
Figure 1 — Clip balance weight assembly terminology
3.1.1
weight
material of a specified mass with contours to conform to the surface of the rim flange (3.3)
Note 1 to entry: The material is recommended to be free of lead.
3.1.2
clip
specially formed metal affixed to the weight (3.1.1) to mount the balance weight on the rim flange (3.3)
3.1.3
spur
optional part of a clip (3.1.3) that protrudes from its surface interfacing with the rim flange (3.3)
3.1.4
balance weight coating
non-corrosive material coating to avoid corrosion
EXAMPLE Polyester, nylon.
3.1.5
balance weight key dimensions
dimensions that are essential for fitting the balance weight (3.1.1) on the rim flange (3.3)
2 © ISO 2021 – All rights reserved

3.1.6
balance weight size
size determined by the magnitude of the balance weight (3.1.1) mass
Note 1 to entry: Balance weight size is expressed in grams.
3.1.7
balance weight retention force
static force required to remove the balance weight (3.1.1) from the rim flange (3.3)
Note 1 to entry: Balance weight retention force is expressed in newtons.
3.1.8
balance weight retention
ability of the balance weight (3.1.1) to maintain its secure position on the rim flange (3.3) in various
service conditions
3.1.9
interference
measure of balance weight (3.1.1) press fit computed as the difference between the flange thickness and
the weight gap
3.2
adhesive balance weight assembly
assembly of the weight portion (3.2.1) and the adhesive portion, which is intended for mounting on the
rim to balance the tyre/wheel assembly about its axis of rotation and thus minimize vibrations due to
the rotation of the tyre/wheel assembly
Note 1 to entry: Figure 2 gives the terminology and nomenclature of
...