Technical Information

Tyre Identification

Tyre Identification

The marking on the side of the tyre tells us the basic size of the tyre, the rim diameter, and the width of the rim.

CSW OD RD
Nominal cross section width expressed in mm Nominal external diameter expressed in mm Nominal rim diameter expressed in inches
240 640 18
CSW Aspect Ratio (AR) R RD
Nominal cross section width expressed in mm The ratio between the section height and the nominal section width (H/CSW) in mm Radial construction Nominal rim diameter expressed in inches
205 65 R 15

Tyre Sizing

Rally Tyre Sizing

E.g. 205/65 R 15

Where

205 is the CSW of the tyre in mm
65 is the aspect ratio
R is radial construction
15 is the nominal rim diameter in inches

Race Tyre Sizing (Clasification 1)

E.g. 200/540-13

Where

205 is the TW of the tyre in mm
540 is the OD of the tyre in mm
13 is the nominal rim diameter in inches

Race Tyre Sizing (Clasification 2)

E.g. 240/640-18

Where

240 is the CSW of the tyre in mm
640 is the OD of the tyre in mm
18 is the nominal rim diameter in inches