Tyre & Rims

Sidewall Markings
On the sidewall of a tyre you will find various codes and markings. The list below aims to simplify the coding system and allow you, the user, to understand the valuable information imprinted on the sidewall.

Tyre Sizes
Tyre sizes are made up of a number of different numbers and letters. For example tyre size 175/70 R 13 82 T is made up of the following information:

175- The tyre section width in millimetres
70- The aspect ratio in % (the height of the sidewall in percentage of tyre width)
R- Denotes the tyre's construction type - in this case it's a radial
13- Rim diameter in inches
82- Load Index
T- Speed Rating

Tyre Age
Tyres carry a four digit age code on the sidewall indicating the week and year of manufacture. For example '0307' means the tyre was manufactured in d 3rd week of 2007.

Other Markings
M&S - Identifies Mud and Snow tyres

DOT Codes - Coding satisfying the requirements of the US Department of Transportation contain a mixture of letters and numbers such as DOT DVDE MTA 129

E-Marks - Tyres for sale in the European Community must carry an E -Mark in accordance with ECE Reg 30 - eg E4 027550

Speed Ratings
All tyres carry a speed symbol in the form of a letter indicating the maximum speed for which the tyre is intended. The table below shows which speed goes with each letter.

Speed symbol (Maximum speed):
N- 140km/h (87mph)
P- 150km/h (93mph)
Q- 160km/h (99mph)
R- 170km/h (106mph)
S- 180km/h (112mph)
T- 190km/h (118mph)
H- 210km/h (130mph)
V- 240km/h (149mph)
W- 270km/h (168mph)
Y- 300km/h (186mph)

Speed category (Maximum speed):
ZR- 240km/h and above (149mph and above)

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