ISO 5751-1:2001

Motorcycle tyres and rims (metric series) — Part 1: Design guides

Pneumatiques et jantes pour motocycles (série millimétrique) — Partie 1: Guide de conception

General Information

• Status: Withdrawn
• Publication Date: 19-Dec-2001
• Withdrawal Date: 19-Dec-2001
• ICS: 83.160.10 - Road vehicle tyres
• Technical Committee: ISO/TC 31/SC 10 - Cycle, moped, motorcycle tyres and rims
• Drafting Committee: ISO/TC 31/SC 10 - Cycle, moped, motorcycle tyres and rims
• Current Stage: 9599 - Withdrawal of International Standard
• Completion Date: 24-Nov-2004

Relations

• Revised: ISO 5751-1:2004 - Motorcycle tyres and rims (metric series) — Part 1: Design guides
• Effective Date: 15-Apr-2008
• Revises: ISO 5751-1:1994 - Motorcycle tyres and rims (metric series) — Part 1: Design guides
• Effective Date: 15-Apr-2008
• Revises: ISO 5751-1:1994/Amd 1:1999 - Motorcycle tyres and rims (metric series) — Part 1: Design guides — Amendment 1
• Effective Date: 15-Apr-2008

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 5751-1
Fifth edition
2001-12-15

Motorcycle tyres and rims (metric series) —
Part 1:
Design guides
Pneumatiques et jantes pour motocycles (séries millimétriques) —
Partie 1: Guide de conception




Reference number
ISO 5751-1:2001(E)
©
ISO 2001

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ISO 5751-1:2001(E)
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ii © ISO 2001 – All rights reserved

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ISO 5751-1:2001(E)
Contents Page
Foreword.iv
1 Scope .1
2 Normative references.1
3 Terms and definitions .1
4 Tyre designation .1
5 Tyre dimensions .5
6 Tread configurations.7
7 Tyre load-carrying capacity.8
8 Speed symbols .10
9 Centrifugal radius .11
Annex A (informative) Guideline values for metric series .12
Bibliography.14

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ISO 5751-1:2001(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
The main task of technical committees is to prepare International Standards. Draft International Standards adopted
by the technical committees are circulated to the member bodies for voting. Publication as an International
Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this part of ISO 5751 may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 5751-1 was prepared by Technical Committee ISO/TC 31, Tyres, rims and valves, Subcommittee SC 10,
Cycle, moped, motorcycle tyres and rims.
This fifth edition cancels and replaces the fourth edition (ISO 5751-1:1994), which has been technically revised.
ISO 5751 consists of the following parts, under the general title Motorcycle tyres and rims (metric series):
 Part 1: Design guides
 Part 2: Tyre dimensions and load-carrying capacities
 Part 3: Range of approved rim contours
Annex A of this part of ISO 5751 is for information only.
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INTERNATIONAL STANDARD ISO 5751-1:2001(E)

Motorcycle tyres and rims (metric series) —
Part 1:
Design guides
1 Scope
This part of ISO 5751 gives guidelines for the design and specifies the designation, the calculation of dimensions
and the load-carrying capacity of metric-series motorcycle tyres.
This part of ISO 5751 is applicable to motorcycle tyres with a reduced height/width ratio (100 and lower) that can
be fitted on cylindrical bead seat rims or 5° tapered bead seat rims. It is also applicable to other concepts of tyre
and rim, in which case, however, the appropriate rim/section ratios and coefficients will have to be established.
NOTE See ISO 4249 for requirements covering motorcycle tyres and rims (code-designated series) of rim diameter code
13 and above, and ISO 6054 for those of code 12 and below.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of
this part of ISO 5751. For dated references, subsequent amendments to, or revisions of, any of these publications
do not apply. However, parties to agreements based on this part of ISO 5751 are encouraged to investigate the
possibility of applying the most recent editions of the normative documents indicated below. For undated
references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain
registers of currently valid International Standards.
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
ISO 4251-3, Tyres (ply rating marked series) and rims for agricultural tractors and machines — Part 3: Rims
3 Terms and definitions
For the purposes of this part of ISO 5751, the terms and definitions given in ISO 4223-1 apply.
4 Tyre designation
4.1 General
The designation of the tyre shall be shown on its sidewall and shall include the following markings, placed close to
each other:
 size and construction (see 4.2);
 service description (see 4.3).
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ISO 5751-1:2001(E)
4.2 Size and construction
4.2.1 Characteristics
The size and construction characteristics shall be indicated as follows:
Nominal Nominal Tyre Nominal
section aspect construction rim diameter
§§§§
width ratio code code
4.2.2 Nominal section width
The nominal section width shall be expressed in millimetres.
4.2.3 Nominal aspect ratio
The nominal aspect ratio shall be expressed as a percentage. It shall be a multiple of 10 for aspect ratios 70 and
higher, and a multiple of 5 for aspect ratios lower than 70.
4.2.4 Tyre construction code
The tyre construction code shall be
 “B” for bias belted type constructions,
 “-” for diagonal ply tyres, and
 “R” for radial ply tyres.
NOTE 1 See also 4.4.3. Other codes will be established for new concepts (constructions) of tyres.
NOTE 2 The term “bias belted construction” describes a pneumatic tyre structure of diagonal (bias ply) type in which the
carcass is restricted by a substantially inextensible circumferential belt
NOTE 3 With reference to the definition of radial ply tyre given in ISO 4223-1, for the purposes of this part of ISO 5751,
“substantially at 90°” means angles between 70° and 90° as measured from the centreline of the tread.
4.2.5 Nominal rim diameter
The nominal rim diameter shall normally be expressed by a code (see Table 1). However, it shall be expressed in
millimetres for new and future concepts where the application either of existing tyres on new-concept rims or of
new-concept tyres on existing rims would be incompatible.
4.3 Service description
The characteristics shall be indicated as follows:
Load index Speed symbol
The load index is a numerical code associated with the maximum load a tyre can carry at the speed indicated by its
speed symbol under the conditions specified in clause 7 (see Table 3).
The speed symbol indicates the speed category in which the tyre can carry the load corresponding to its load index
under the service conditions specified in clause 7 (see Table 4).
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ISO 5751-1:2001(E)
Table 1 — Nominal rim diameter and rim width codes
Dimensions in millimetres
Nominal rim diameter code Rim width code
Code Nominal rim diameter Code Measuring rim width
D R
r m
8 203 1.50 38
10 254 1.60 40,5
12 305 1.85 47
13 M/C 330 2.15 55
14 M/C 356 2.50 63,5
15 M/C 381 2.75 70
16 M/C 406 3.00 76
17 M/C 432 3.50 89
18 M/C 457 3.75 95
19 M/C 483 4.00 101,5
20 M/C 508 4.50 114,5
21 M/C 533 5.00 127
23 M/C 584 5.50 139,5
6.00 152,5
6.25 159
6.50 165
7.00 178

4.4 Other service characteristics
4.4.1 In the case of tubeless tyres, the marking “TUBELESS” shall be shown on the tyre.
4.4.2 In the case of a preferred direction of rotation of the tyre, an arrow shall be used to indicate that direction.
4.4.3 Tyres designed for vehicles having a maximum speed capacity in excess of 240 km/h shall be identified by
means of the code letters
 “VB” or “ZB” for bias-belted construction,
 “VR” or “ZR” for radial construction,
where “ZB” and “ZR” should be used for newly designed motorcycles with a maximum speed over 240 km/h.
This identification shall be placed inside the tyre designation (see 4.2) instead of in the tyre construction code.
For speed category “V”, “VB” or “VR” tyres suitable for speeds of over 240 km/h, a service description with the
speed symbol “V” shall be marked in parentheses.
EXAMPLE 1 120/60 VR 17 (55 V)
For speed category “ZB” or “ZR” tyres suitable for speeds up to 270 km/h, a service description with the speed
symbol “W” shall be marked.
EXAMPLE 2 120/60 ZR 17 55 W
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ISO 5751-1:2001(E)
If the same tyres are suitable for speeds of over 270 km/h, the service description shall be marked in parentheses.
EXAMPLE 3 120/60 ZR 17 (55 W)
4.4.4 For nominal rim diameter codes 13 and above, the suffix “M/C” shall be added to the size and construction
marking, to prevent confusion and misfitting of motorcycle tyres on rims having the same nominal diameters but
designed primarily for passenger car tyres in accordance with ISO 4000-2 or agricultural tyres in accordance with
ISO 4251-3.
4.4.5 The maximum speed approved by the tyre manufacturer may be marked on the tyre.
EXAMPLE “V250” to identify a maximum speed of 250 km/h.
4.4.6 The symbol “MST” may be used to identify special service tyres.
4.4.7 The symbol “DP” may be used to identify tread type C tyres.
4.5 Examples
4.
...