ISO/PRF 18164

Motorcycle tyres rolling resistance measurement methods — Single point test

ISO 18164 specifies methods for measuring rolling resistance, under controlled laboratory conditions, for new pneumatic tyres designed primarily for use on motorcycles. The relationship between values obtained and the fuel economy of the vehicle is undetermined, and such values are not intended to be used to indicate levels of performance or quality.

Titre manque

L'ISO 18164:2005 prescrit des méthodes de mesure de la résistance au roulement, dans des conditions de laboratoire maîtrisées, pour des pneumatiques neufs conçus essentiellement pour être utilisés sur des voitures particulières, des camions, des autobus et des motocycles. Il n'est pas établi de relation entre les valeurs ainsi obtenues et les économies de carburant des véhicules, et de telles valeurs ne sont pas destinées à être exploitées pour indiquer des niveaux de performance ou de qualité. L'ISO 18164:2005 est applicable à tous les pneumatiques pour voitures particulières, camions, autobus et motocycles.

General Information

• Status: Not Published
• ICS: 83.160.01 - Tyres in general
• ICS: 83.160.10 - Road vehicle tyres
• Technical Committee: ISO/TC 31 - Tyres, rims and valves
• Drafting Committee: ISO/TC 31/WG 6 - Rolling resistance (highway tyres)
• Current Stage: 5020 - FDIS ballot initiated: 2 months. Proof sent to secretariat
• Start Date: 04-Jun-2026
• Completion Date: 06-Jun-2026

Relations

• Revises: ISO 28580:2018 - Passenger car, truck and bus tyre rolling resistance measurement method — Single point test and correlation of measurement results
• Effective Date: 07-Sep-2024
• Revises: ISO 18164:2005 - Passenger car, truck, bus and motorcycle tyres — Methods of measuring rolling resistance
• Effective Date: 31-Aug-2024

Overview

ISO/PRF 18164: Motorcycle tyres rolling resistance measurement methods - Single point test is an international standard developed by the International Organization for Standardization (ISO), specifically within Technical Committee ISO/TC 31 (Tyres, rims and valves). This standard outlines laboratory methods for measuring the rolling resistance of new pneumatic motorcycle tyres using a single-point test approach.

The standard targets tyres designed primarily for motorcycles and provides detailed methodologies and conditions to ensure test repeatability and comparability between different laboratories. While rolling resistance is a crucial property reflecting energy loss as tyres roll, ISO/PRF 18164 does not establish a direct relationship between measured rolling resistance values and motorcycle fuel economy, nor does it use these values as an indicator of performance or quality.

---

Key Topics

• Rolling Resistance Definition: Energy loss per unit distance as a tyre rolls, typically measured in newtons (N).
• Single Point Test Method: Focuses on controlled laboratory measurement of rolling resistance at a specific test speed and load, standardizing results for consistency.
• Test Methods: The standard permits several measurement techniques:
  • Force method: Measuring reaction force at the tyre spindle.
  • Torque method: Monitoring input torque at the drum.
  • Power method: Tracking power input to the test drum.
  • Deceleration method: Assessing deceleration rates of drum-tyre assemblies.
• Test Equipment and Environmental Control: Specifies requirements for test drum dimensions, surface texture, rim type, load alignment, instrumentation accuracy, and thermal environment.
• Data Interpretation and Correction: Includes procedures for calculating rolling resistance, correcting results for temperature and drum diameter variances, and establishing the rolling resistance coefficient.
• Repeatability and Tolerance: Provides stringent equipment tolerance and measurement standards to achieve reproducibility and data reliability.

---

Applications

The methods described in ISO/PRF 18164 are widely applicable in the motorcycle industry and among tyre manufacturers, researchers, and regulatory agencies:

• Product Development: Tyre manufacturers use these methods to benchmark and optimize the rolling resistance properties of new motorcycle tyre designs under standardized conditions.
• Comparative Testing: Laboratories and testing organizations employ the standard to generate comparable rolling resistance data across different tyre models or brands, facilitating transparent product comparison.
• Quality Assurance: By adhering to the defined test conditions and tolerances, manufacturers can ensure consistent tyre quality and identify anomalies in production.
• Research and Innovation: Academic and industrial researchers rely on ISO/PRF 18164 for reproducible measurement frameworks in studies surrounding tyre materials, tread design, and energy efficiency.
• Industry Standards Compliance: Adoption of this ISO standard supports compliance with international best practices for tyre testing, aiding global market access.

Note: Rolling resistance values measured under this standard are not to be used as direct indicators of motorcycle fuel economy, performance ratings, or overall product quality.

---

Related Standards

For accurate and comprehensive tyre testing, the following related ISO standards are relevant:

• ISO 4223-1:2017: Definitions of terms used in the tyre industry, offering a common vocabulary for pneumatic tyres.
• ISO 28580: (Historic) Rolling resistance measurement methods for passenger car, truck, and bus tyres.
• ISO 80000-1:2022: General rules for quantities and units applicable to measurement rounding and reporting.

Organizations and laboratories implementing ISO/PRF 18164 are encouraged to consult these documents to ensure alignment with current tyre industry terminology, reporting practices, and supplementary measurement protocols.

---

By adopting ISO/PRF 18164, industry professionals gain a harmonized and precise method for assessing the rolling resistance of motorcycle tyres, contributing to robust product evaluation and facilitating fair comparison within the global marketplace.

Standards Content (Sample)

International
Standard
ISO 18164
Second edition
Motorcycle tyres rolling resistance
measurement methods — Single
point test
PROOF/ÉPREUVE
Reference number
ISO 18164:2026(en) © ISO 2026
ISO 18164:2026(en)
© ISO 2026
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
PROOF/ÉPREUVE
ii
ISO 18164:2026(en)
Contents Page
Foreword .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Test methods . 2
5 Test equipment . 2
5.1 Drum specifications .2
5.1.1 Diameter .2
5.1.2 Surface .3
5.1.3 Width .3
5.2 Test rim .3
5.3 Load, alignment, control and instrumentation accuracies .3
5.4 Thermal environment .3
5.4.1 Reference conditions .3
5.4.2 Alternative conditions .3
5.4.3 Drum surface temperature .3
6 Test conditions . 3
6.1 General .3
6.2 Test speeds .3
6.2.1 Single test speed .3
6.3 Test load .4
6.4 Test inflation pressure .4
6.5 Duration and speed .4
7 Test procedure . 4
7.1 General .4
7.2 Thermal conditioning .4
7.3 Pressure adjustment .4
7.4 Warm-up .4
7.5 Measurement and recording .4
7.6 Measurement of parasitic losses .5
7.6.1 General .5
7.6.2 Skim test reading .5
7.6.3 Machine reading .6
7.6.4 Deceleration method.6
7.7 Allowance for machines exceeding sigma m criterion .6
8 Data interpretation . 6
8.1 Calculation of parasitic losses .6
8.1.1 General .6
8.1.2 Force method at tyre spindle .7
8.1.3 Torque method at drum axis .7
8.1.4 Power method at drum axis .7
8.1.5 Deceleration method.7
8.2 Rolling resistance calculation .8
8.2.1 General .8
8.2.2 Force method at tyre spindle .8
8.2.3 Torque method at drum axis .8
8.2.4 Power method at drum axis .8
8.2.5 Deceleration method.8
9 Data analysis . 9
9.1 Rolling resistance coefficient .9
9.2 Temperature correction .9
9.3 Drum diameter correction .9
PROOF/ÉPREUVE
iii
ISO 18164:2026(en)
9.4 Measurement result and rounding .10
Annex A (informative) Measurement methods of moment of inertia for drum and tyre
assembly — Deceleration method .11
Annex B (normative) Test equipment tolerances .16
Annex C (informative) Example for machine drift evaluation . 19
Bibliography .21
PROOF/ÉPREUVE
iv
ISO 18164:2026(en)
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 document 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).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
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.
ISO 18164 was prepared by Technical Committee ISO/TC 31, Tyres, rims and valves.
This second edition of ISO 18164 cancels and replaces ISO 18164:2005 and ISO 28580:2018, which have
been technically revised.
The main change is as follows:
— the measuring methods for passenger car, truck and bus tyres, and the optional test methods of the
former Annex B have been removed.
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.
PROOF/ÉPREUVE
v
International Standard ISO 18164:2026(en)
Motorcycle tyres rolling resistance measurement methods —
Single point test
1 Scope
This document specifies methods for measuring rolling resistance, under controlled laboratory conditions,
for new pneumatic tyres designed primarily for use on motorcycles. The relationship between values
obtained and the fuel economy of the vehicle is undetermined, and such values are not intended to be used to
indicate levels of performance or quality.
This document applies to motorcycle tyres.
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 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 4223-1 and the following apply.
ISO and IEC maintain terminology 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
rolling resistance
F
r
loss of energy (or energy consumed) per unit of distance travelled
.
Note 1 to entry: The SI unit conventionally used for the rolling resistance is the newton metre per metre (N m/m). This
is equivalent to a drag force in newtons (N).
3.2
rolling resistance coefficient
C
r
ratio of the rolling resistance to the load on the tyre
Note 1 to entry: Rolling resistance is measured in newtons (N).
Note 2 to entry: Load on the tyre is measured in kilonewtons (kN).
Note 3 to entry: Although this quantity is dimensionless, it is conventionally expressed in N/kN.
PROOF/ÉPREUVE
ISO 18164:2026(en)
3.4
parasitic loss
loss of energy (or energy consumed) per unit distance excluding internal tyre losses, and attributable to
aerodynamic loss of the different rotating elements of the test equipment, bearing friction and other sources
of systematic loss which can be inherent in the measurement
Note 1 to entry: Depending on the method used, the aerodynamic loss of the tyre is possibly or possibly not included
in the parasitic loss.
3.5
skim test reading
type of parasitic loss measurement, in which the tyre is kept rolling, without slippage, while reducing the
tyre load to a level at which energy loss within the tyre itself is virtually zero
3.6
machine reading
type of parasitic loss measurement, involving losses of the test machine, exclusive of losses in the rotating
spindle bearing, which carries the tyre and rim, and aerodynamic losses
3.7
moment of inertia
ratio of the torque applied to the tyre to the annular acceleration on the tyre
Note 1 to entry: See Annex A.
4 Test methods
The following are alternative measurement methods. The choice of an individual method is left to the tester.
For each method, the test measurements shall be converted to a force acting at the tyre/drum interface.
a) Force method: the reaction force measured at the tyre spindle. This measured value also includes the
bearing losses of the tyre spindle and the aerodynamic losses of the tyre and the wheel.
b) Torque method: the torque input measured at the test drum (see NOTE).
c) Power method: the measurement of the power input to the test drum (see NOTE).
d) Deceleration method: the measurement of deceleration of the test drum and tyre assembly (see NOTE).
NOTE This measured value also includes the bearing and aerodynamic losses of the wheel, the tyre and the drum,
losses that are also to be considered.
5 Test equipment
5.1 Drum specifications
5.1.1 Diameter
The test dynamometer shall have a cylindrical flywheel (drum) with a diameter of at least 1,5 m (reference
drum diameter: 1,7 m).
The results are different for different diameters; see 9.3 for drum diameter correction for comparisons, if
necessary.
NOTE Historically, the measurement of the fore and aft (longitudinal) force on a flat surface machine has been
shown to be quite difficult since this force is very small relative to other forces being measured. If a flat surface
machine is used, care must be taken to correlate the data with the reference drum diameter in order to assure accurate
results.
PROOF/ÉPREUVE
ISO 18164:2026(en)
5.1.2 Surface
The surface of the drum shall be smooth steel or textured and shall be kept clean. For the textured drum
surface, see B.6.
5.1.3 Width
The width of the drum test surface shall exceed the width of the test tyre tread.
5.2 Test rim
The tyre shall be mounted on a test rim, as specified in Annex B.
5.3 Load, alignment, control and instrumentation accuracies
Measurement of these parameters shall be sufficiently accurate and precise to provide the required test
data. The specific and respective values are shown in Annex B.
5.4 Thermal environment
5.4.1 Reference conditions
The reference ambient temperature, as measured on the rotational axis of the tyre, 1 m away from the plane
touching the nearest tyre sidewall, shall be 25 °C.
5.4.2 Alternative conditions
If the reference temperature cannot be obtained, the rolling resistance measurement shall be corrected to
standard temperature conditions in accordance with 9.2.
5.4.3 Drum surface temperature
Care should be taken to ensure that the temperature of the test drum surface is approximately the same as
the ambient temperature at the beginning of the test.
6 Test conditions
6.1 General
The test consists of a measurement of rolling resistance in which the tyre is inflated and the inflation
pressure is allowed to build up (i.e. “capped air”).
6.2 Test speeds
6.2.1 Single test speed
The value shall be obtained at a drum speed as shown in Table 1. Speed is in kilometres per hour.
Table 1 — Test speeds
Tyre type Motorcycle
Load index All All
Speed symbol L and below Above L
Speed 50 80
PROOF/ÉPREUVE
ISO 18164:2026(en)
6.3 Test load
The standard test load shall be computed from the values shown in Table 2 and shall be kept within the
tolerances specified in Annex B.
Table 2 — Test loads and inflation pressures
Tyre type Motorcycle
Reinforced or
Standard load
extra load
Load
% of maximum 65 80
load capacity
Inflation pressure
200 250
kPa
6.4 Test inflation pressure
The inflation pressure shall be in accordance with those shown in Table 2 and shall be capped with the
accuracy specified in B.4.1.
6.5 Duration and speed
When the deceleration method is selected, the following requirements apply:
a) for duration, ∆t, the time increments shall not exceed 0,5 s;
b) any variation of the test drum speed shall not exceed 1 km/h.
7 Test procedure
7.1 General
The test procedure steps described below shall be followed in the sequence given.
7.2 Thermal conditioning
Place the inflated tyre in the thermal environment of the test location for the time necessary to achieve
thermal equilibrium, which is generally reached after 3 h.
7.3 Pressure adjustment
After thermal conditioning, the inflation pressure shall be adjusted to the test pressure, and verified 10 min
after the adjustment is made.
7.4 Warm-up
The tyre shall be run at constant test speed until reaching a stabilized steady-state value of rolling resistance.
Warm-up duration is 30 minutes for all nominal rim diameter codes.
7.5 Measurement and recording
The following shall be measured and recorded (see Figure 1):
a) test speed, U ;
n
b) load on the tyre normal to the drum surface, L ;
m
PROOF/ÉPREUVE
ISO 18164:2026(en)
c) test inflation pressure:
1) initial, as defined in 6.4;
2) final, inflation;
d) the driving torque on the drive shaft, T , the tyre spindle force, F , the input power, V × A, or the
t t
deceleration of the test drum-tyre-wheel assembly,  t, depending on the method;
e) distance from the tyre axle to the drum outer surface under steady-state conditions, r (see 8.1.2);
L
f) ambient temperature, t ;
amb
g) test drum radius, R;
h) rolling resistance force, F ;
r
i) test method chosen;
j) test rim (designation and material).
Key
1 tyre
2 drum
NOTE The system assumes no bearing and aerodynamic losses.
Figure 1 — Free-body diagram of tyre-drum system
7.6 Measurement of parasitic losses
7.6.1 General
Determine parasitic losses by one of the procedures given in 7.6.2 to 7.6.4.
7.6.2 Skim test reading
a) Reduce the load to maintain the tyre at the test speed without slippage. The load
...

ISO/DISPRF 18164:2025(en)
ISO/TC 31
Secretariat: ANSI
Date: 2025-12-192026-06-04
Motorcycle tyres rolling resistance measurement methods —
Single point test
Pneumatiques pour motocycles — Méthodes de mesure de la résistance au roulement

PROOF
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'sISO’s member body in the country of the requester.
ISO Copyright Officecopyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: + 41 22 749 01 11
Email:
E-mail: [e-mail]
Website: www.iso.org
Published in Switzerland.
iv
ISO/DISPRF 18164:20252026(en)
Contents
Foreword . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Test methods . 2
5 Test equipment . 3
5.1 Drum specifications . 3
5.2 Test rim . 3
5.3 Load, alignment, control and instrumentation accuracies . 3
5.4 Thermal environment . 3
6 Test conditions . 3
6.1 General . 3
6.2 Test speeds . 4
6.3 Test load . 4
6.4 Test inflation pressure . 4
6.5 Duration and speed . 4
7 Test procedure . 5
7.1 General . 5
7.2 Thermal conditioning . 5
7.3 Pressure adjustment . 5
7.4 Warm-up . 5
7.5 Measurement and recording . 5
7.6 Measurement of parasitic losses . 7
7.7 Allowance for machines exceeding sigma m criterion . 7
8 Data interpretation . 8
8.1 Calculation of parasitic losses . 8
8.2 Rolling resistance calculation . 9
9 Data analysis . 10
9.1 Rolling resistance coefficient . 10
9.2 Temperature correction . 11
9.3 Drum diameter correction . 11
9.4 Measurement result and rounding . 11
Annex A (informative) Measurement methods of moment of inertia for drum and tyre
assembly — Deceleration method . 13
Annex B (normative) Test equipment tolerances . 22
Annex C (informative) Example for machine drift evaluation . 25
Bibliography . 28

v
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 document 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).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent rights
in respect thereof. As of the date of publication of this document, ISO had not received notice of (a) patent(s)
which may be required to implement this document. However, implementers are cautioned that this may not
represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
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.
ISO 18164 was prepared by Technical Committee ISO/TC 31, Tyres, rims and valves.
This second edition of ISO 18164 cancels and replaces ISO 18164:2005 and ISO 28580:2018, which have been
technically revised.
The main change is as follows:
— — the measuring methods for passenger car, truck and bus tyres, and the optional test methods of the
former Annex BAnnex B have been removed.
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.

vi
DRAFT International Standard ISO/DIS 18164:2025(en)

Motorcycle tyres — Methods of measuring rolling resistance
measurement methods — Single point test
1 Scope
This document specifies methods for measuring rolling resistance, under controlled laboratory conditions, for
new pneumatic tyres designed primarily for use on motorcycles. The relationship between values obtained
and the fuel economy of the vehicle is undetermined, and such values are not intended to be used to indicate
levels of performance or quality.
This document applies to motorcycle tyres.
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 4223--1:2017, 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 4223-1 and the following apply.
ISO and IEC maintain terminology 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 3.1
rolling resistance
F
r
loss of energy (or energy consumed) per unit of distance travelled
NOTE Note 1 to entry: The SI unit conventionally used for the rolling resistance is the newton metre per metre
.
(N m/m). This is equivalent to a drag force in newtons (N).
3.2 3.2
rolling resistance coefficient
C
r
ratio of the rolling resistance to the load on the tyre
Note 1 to entry: Rolling resistance is measured in newtons (N).
Note 2 to entry: Load on the tyre is measured in kilonewtons (kN).
Note 3 to entry: Although this quantity is dimensionless, it is conventionally expressed in N/kN.
3.3 3.4
parasitic loss
loss of energy (or energy consumed) per unit distance excluding internal tyre losses, and attributable to
aerodynamic loss of the different rotating elements of the test equipment, bearing friction and other sources
of systematic loss which can be inherent in the measurement
Note 1 to entry: Depending on the method used, the aerodynamic loss of the tyre mayis possibly or maypossibly not be
included in the parasitic loss.
3.4 3.5
skim test reading
type of parasitic loss measurement, in which the tyre is kept rolling, without slippage, while reducing the tyre
load to a level at which energy loss within the tyre itself is virtually zero
3.5 3.6
machine reading
type of parasitic loss measurement, involving losses of the test machine, exclusive of losses in the rotating
spindle bearing, which carries the tyre and rim, and aerodynamic losses
3.6 3.7
moment of inertia
ratio of the torque applied to the tyre to the annular acceleration on the tyre
Note 1 to entry: See Annex AAnnex A.
4 Test methods
The following are alternative measurement methods. The choice of an individual method is left to the tester.
For each method, the test measurements shall be converted to a force acting at the tyre/drum interface.
a) a) Force method: the reaction force measured at the tyre spindle. This measured value also
includes the bearing losses of the tyre spindle and the aerodynamic losses of the tyre and the wheel.
b) b) Torque method: the torque input measured at the test drum (see NOTE).
c) c) Power method: the measurement of the power input to the test drum (see NOTE).
d) d) Deceleration method: the measurement of deceleration of the test drum and tyre assembly (see
NOTE).
NOTE This measured value also includes the bearing and aerodynamic losses of the wheel, the tyre and the drum,
losses that are also to be considered.

ISO/DISPRF 18164:20252026(en)
5 Test equipment
5.1 Drum specifications
5.1.1 Diameter
The test dynamometer shall have a cylindrical flywheel (drum) with a diameter of at least 1,5 m (reference
drum diameter: 1,7 m).
The results are different for different diameters; see 9.39.3 for drum diameter correction for comparisons, if
necessary.
NOTE Historically, the measurement of the fore and aft (longitudinal) force on a flat surface machine has been shown
to be quite difficult since this force is very small relative to other forces being measured. If a flat surface machine is used,
care must be taken to correlate the data with the reference drum diameter in order to assure accurate results.
5.1.2 Surface
The surface of the drum shall be smooth steel or textured and shall be kept clean. For the textured drum
surface, see B.6B.6.
5.1.3 Width
The width of the drum test surface shall exceed the width of the test tyre tread.
5.2 Test rim
The tyre shall be mounted on a test rim, as specified in Annex BAnnex B.
5.3 Load, alignment, control and instrumentation accuracies
Measurement of these parameters shall be sufficiently accurate and precise to provide the required test data.
The specific and respective values are shown in Annex BAnnex B.
5.4 Thermal environment
5.4.1 Reference conditions
The reference ambient temperature, as measured on the rotational axis of the tyre, 1 m away from the plane
touching the nearest tyre sidewall, shall be 25 °C.
5.4.2 Alternative conditions
If the reference temperature cannot be obtained, the rolling resistance measurement shall be corrected to
standard temperature conditions in accordance with 9.29.2.
5.4.3 Drum surface temperature
Care should be taken to ensure that the temperature of the test drum surface is approximately the same as the
ambient temperature at the beginning of the test.
6 Test conditions
6.1 General
The test consists of a measurement of rolling resistance in which the tyre is inflated and the inflation pressure
is allowed to build up (i.e. “capped air”).
6.2 Test speeds
6.2.1 Single test speed
The value shall be obtained at a drum speed as shown in Table 1Table 1. . Speed is in kilometerskilometres
per hour.
Table 1 — Test speeds
Tyre type Motorcycle
Load index All All
Speed symbol L and below Above L
Speed 50 80
6.3 Test load
The standard test load shall be computed from the values shown in Table 2Table 2 and shall be kept within
the tolerances specified in Annex BAnnex B.
Table 2 — Test loads and inflation pressures
Tyre type Motorcycle
Reinforced or
Standard load
extra load
Load
% of maximum 65 80
load capacity
Inflation
pressure 200 250
kPa
6.4 Test inflation pressure
The inflation pressure shall be in accordance with those shown in Table 2Table 2 and shall be capped with the
accuracy specified in B.4.1B.4.1.
6.5 Duration and speed
When the deceleration method is selected, the following requirements apply:
a) a) for duration, 𝛥𝛥𝛥𝛥, the time increments shall not exceed 0,5 s;
b) b) any variation of the test drum speed shall not exceed 1 km/h.

ISO/DISPRF 18164:20252026(en)
7 Test procedure
7.1 General
The test procedure steps described below shall be followed in the sequence given.
7.2 Thermal conditioning
Place the inflated tyre in the thermal environment of the test location for the time necessary to achieve thermal
equilibrium, which is generally reached after 3 h.
7.3 Pressure adjustment
After thermal conditioning, the inflation pressure shall be adjusted to the test pressure, and verified 10 min
after the adjustment is made.
7.4 Warm-up
The tyre shall be run at constant test speed until reaching a stabilized steady-state value of rolling resistance.
Warm-up duration is 30 minutes for all nominal rim diameter codes.
7.5 Measurement and recording
The following shall be measured and recorded (see Figure 1Figure 1):):
a) a) test speed, U ;
n
b) b) load on the tyre normal to the drum surface, L ;
m
c) c) test inflation pressure:
1) 1) initial, as defined in 6.46.4;;
2) 2) final, inflation;
d) d) the driving torque on the drive shaft, T , the tyre spindle force, F , the input power, V × A, or the
t t
deceleration of the test drum-tyre-wheel assembly, 𝛥𝛥𝛥𝛥⁄𝛥𝛥𝛥𝛥, depending on the method;
e) e) distance from the tyre axle to the drum outer surface under steady-state conditions, r (see
L
8.1.28.1.2););
f) f) ambient temperature, t ;
amb
g) g) test drum radius, R;
h) h) rolling resistance force, F ;
r
i) i) test method chosen;
j) j) test rim (designation and material).
Key
1 tyre
2 drum
ISO/DISPRF 18164:20252026(en)
Figure 1 — Free-body diagram of tyre-drum system
NOTE The system assumes no bearing and aerodynamic losses.
Figure 1 — Free-body diagram of tyre-drum system
7.6 Measurement of parasitic losses
7.6.1 General
Determine parasitic losses by one of the procedures given in 7.6.27.6.2 to 7.6.47.6.4.
7.6.2 Skim test reading
a) a) Reduce the load to maintain the tyre at the test speed without slippage. The load values should
be as follows: Motorcyclemotorcycle tyres: Tyre, tyre load not to exceed 200 N.
b) b) Record the spindle force, F , input torque, T , or the power, whichever applies.
t , t
c) c) Record the load on the tyre normal to the drum surface, L .
m
NOTE The measured value includes the bearing and aerodynamic losses of the wheel, the tyre and the drum, losses
that are also to be considered.
7.6.3 Machine reading
a) a) Remove the tyre from the drum surface.
b) b) At the test speed, U , record the input torque, T , the power, or the test drum deceleration,
n t
whichever applies.
NOTE The measured value includes the drum losses to be considered.
7.6.4 Deceleration method
a) a) Remove the tyre from the test surface.
⁄ ⁄
b) b) Record the deceleration of the test drum, ,𝛥𝛥𝛥𝛥 𝛥𝛥𝛥𝛥, and that of the unloaded tyre,.,𝛥𝛥𝛥𝛥 𝛥𝛥𝛥𝛥.
𝜊𝜊 𝑝𝑝𝑝𝑝
The speed range for measurement includes the test speed and does not exceed 10 km/h above and 10 km/h
below the test speed.
The measured value includes the bearing and aerodynamic losses of the wheel, the tyre, and the drum losses
which are also to be considered.
NOTE It is known that the spindle and drum bearings friction depends on the applied load and, in
consequence, is different for the loaded system measurement and the free deceleration. But for practical
reasons, this difference maybemay be disregarded.
The speed range of the rolling resistance measurement with loaded tyre shall respect the same condition as
for the parasitic losses measurement as described above.
7.7 Allowance for machines exceeding sigma m criterion
The steps described in 7.47.4 to 7.67.6 shall be carried out one time if the measurement standard deviation,
is not greater than 0,15 N/kN. If the measurement standard deviation exceeds this criterion, the measurement
process shall be repeated n times. The rolling resistance value reported shall be the average of the n
measurements.
8 Data interpretation
8.1 Calculation of parasitic losses
8.1.1 General
The parasitic losses, F , related to the tyre-drum interface expressed in newtons, shall be calculated from the
pl
force F , torque, power or the deceleration, using Formula (1)(1) below.
t
8.1.2 Force method at tyre spindle

𝐹𝐹 =𝐹𝐹 (1 +𝑟𝑟 /𝑅𝑅)
pl t L
(1)
where
Ft is the tyre spindle force in newtons (see 7.6.27.6.2););
rL is the distance from the tyre axis to the drum outer surface under steady state conditions, in metersmetres;
R is the test drum radius, in metersmetres.
8.1.3 Torque method at drum axis
The parasitic losses, F , shall be calculated using Formula (2)Formula (2) below.
pl
F = T /R (2)
pl t
where
Tt is the input torque in newton metersmetres as determined in 7.6.27.6.2 or 7.6.37.6.3;;
R is the test drum radius, in metersmetres.
8.1.4 Power method at drum axis
The parasitic losses, F , shall be calculated using Formula (3)Formula (3) below.
pl
3,6 𝑉𝑉×𝐴𝐴
𝐹𝐹 =
pl
𝑈𝑈
n
(3)
where
V is the electrical potential applied to the machine drive, in volts;
A is the electric current drawn by the machine drive, in amperes;
U is the test drum speed, in kilometersmeterskilometres per hour.
n
8.1.5 Deceleration method
Calculate the parasitic losses, F , in newtons using Formula (4)Formula (4) below
pl
ISO/DISPRF 18164:20252026(en)
(4)
𝐼𝐼 𝛥𝛥𝛥𝛥 𝐼𝐼 𝛥𝛥𝛥𝛥
po
D 𝑣𝑣𝑝𝑝 T
𝐹𝐹 = ( ) + ( )
pl
𝑅𝑅 𝛥𝛥𝛥𝛥 𝑅𝑅 𝛥𝛥𝛥
...