The identification code is engraved in the rim and contains the
most important size data for the rim.
Dimension
Meaning
Example
A
Rim flange to flange width (inches)
6
B
Rim flange shape
J
C
Rim diameter (inches)
16
D
Number of holes
5
E
Covering bead profile
T
F
Dish ET (mm)
49
G
Point at which the maximum lateral runout is measured
H
Center of rim
The code may be present in full or in abbreviated form (e.g. 6 J
16).
Tyres
Each tyre can be identified by its code.
Example: 195/70 R 13 108 L
Code
Meaning
195
Tyre width A (mm)
70
Nominal cross-section ratio height B / width A (%)
R
Type of structure
13
Nominal rim diameter D (inch)
108
Code for load-bearing strength
L
Speed symbol
Types of structure
Type of structure
Code
Diagonal
None
Radial
R
R
B
Speed Data
Speed symbol
(GSY)
Maximum speed
(km/h)
J
100
K
110
L
120
M
130
N
140
P
150
Q
160
R
170
S
180
T
190
U
200
H
210
V
240
W
270
Y
300
ZR
Over 240
Codes for load-bearing strength
Code
Permissible wheel load
(kg)
Permissible axle load
(kg)
74
375
750
75
387
775
76
400
800
77
412
825
78
425
850
79
437
875
80
450
900
81
462
925
82
475
950
83
487
975
84
500
1000
85
515
1030
86
530
1060
87
545
1090
88
560
1120
89
580
1160
90
600
1200
91
615
1230
92
630
1260
93
650
1300
94
670
1340
95
690
1380
96
710
1420
97
730
1460
98
750
1500
99
775
1550
100
800
1600
101
825
1650
102
850
1700
103
875
1750
104
900
1800
105
925
1850
106
950
1900
107
975
1950
108
1000
2000
109
1030
2060
110
1060
2120
A Few Important Terms
Rim flange to flange width
The distance between the rim flanges.
Cross-sectional height
Half the difference between the external diameter and the
nominal diameter of the rims.
Nominal width
The width stated in the tyre size for a pumped up tyre which is
mounted on the theoretically correct rim.
Cross-sectional width
The distance between the outsides of the side walls of a pumped
up tyre, excluding the higher areas caused by lettering, decorative
ribs and abrasion strips.
Overall width
The distance between the outsides of the side walls of a pumped
up tyre, including the higher areas caused by lettering, decorative
ribs and abrasion strips.
External diameter
The diameter of a pumped up tyre at the outermost point of the
running surface.
Nominal cross-section ratio
One hundred times the ratio of the cross-sectional height and
the cross-sectional width of the tyre on its theoretical rim.
Load-bearing strength of tyre
The maximum load-bearing strength of a tyre which is permissible
for specified conditions of use.
Tyre pressure
Tyre pressure refers to the pressure inside the tyre at an
ambient temperature; it does not include the increase in air
pressure caused by the use of the tyre.
Speed symbol
The speed symbol indicates the maximum speed at which the tyre
has the load-bearing strength corresponding to the load-bearing
strength code in the conditions of use specified by the tyre
manufacturer (exception: speeds greater than 210 km/h).
Tyre identification codes
In Europe, the Standard ECE-R 30 applies to vehicle tyres up to
270 km/h. It contains the most important tyre characteristics. In
addition there are some codes for North America.
In the tyre code shown below, item 9: 185/60 R 14 87 T refers to
a radial tyre.
1
Position of the tread wear indicator (TWI), depth 1.6 mm
2
Manufacturer
3
Indication of particular suitability for winter use
4
Description of profile
5
Code for tubeless tyre
6
Relative life expectancy according to US test (180 = 180%)
7
Assessment of braking in the wet (A, B or C) according to US
test
8
Assessment of thermal stability at high speeds (A, B or C)
according to US test
9
Size (185/60 R 14 87 T)
185
Tyre width of tyre in mm (nominal width)
60
Percentage ratio of cross-sectional height to width of tyre
R
Radial construction
14
Rim diameter in inches (")
87
Load index for 545 kg
T
Speed symbol for maximum 190 km/h; for other codes see this
publication.
10
Safety instructions for using or fitting the tyre (US data)
11
Radial construction
12
Number and material of layers in centre of tread and
sidewall
13
Approval mark to European directive ECE-R 30
14
Manufacturer's internal code
15
Indication of maximum permissible load and tyre pressure for
North America
16
DOT mark to comply with American Department of Transportation
requirements
17
DOT code for factory, tyre size and type
18
Date of manufacture (here 1st week of production 2000). This
code consists of 4 figures, two for the week and two for the
year.
