Understanding Tyre Markings

All tyres have information marked on the outside of the tyre outlining the tyre manufacturer, type/design, the maximum weight the tyre can carry, maximum load pressure, speed capacity etc. The information is there to enable us to select the right tyre for our vehicle.

A typical example of markings found on the side of a tyre are 205/55R16 91W.

205 – Indicates the tyre has a nominal section width of 165 millimetres (distance between the outside of an inflated tires sidewalls.

55 – Is the aspect ratio of the tyre, which is the ratio between the section height and section width.

R – Means Radial construction

16 – Is the diameter of the rim which indicates that the example tyre will fit a 16” diameter wheel/alloy.

91 – Is the load index a figure which gives the maximum load the tyre can carry at the specified speed. The figure is used to find the maximum load using a load index scale table which gives us a figure of approx 615kg.