Question and answer
What tyre size do I need?
The easiest way to find out is to check the code on your current tyres. The car’s owner’s manual also states which tyres are suitable.
How do I read a tyre size?
A tyre’s dimensions are expressed in width (in millimetres), height (as a percentage of the width) and rim size (in inches). For example: “215/45R17” refers to tyres that are 215 mm wide, have a sidewall height of 97 mm and fit a 17-inch rim..
Additional factors to consider include the load capacity and the maximum speed. These are not used directly, but are taken from a table. The maximum speed is expressed using letters from M to Z, where M stands for a maximum of 130 km/h and Z for (well) over 250 km/h. The load capacity, also known as the ‘load index’, ranges from 63 (272 kg per tyre) to 121 (1,400 kg per tyre)..
How does this system select a tyre?
The database contains the tyre size, top speed and maximum permissible weight for each car. Potential tyres are displayed based on this information. If several companies offer the same tyres, the most affordable option is automatically selected.
Do I need summer or winter tyres?
Summer tyres are best in summer. They produce little noise, offer optimum grip and can withstand high temperatures. Winter tyres are recommended at temperatures below 7 degrees and have a tread pattern better suited to dispersing water and snow (at the expense of rolling resistance and noise).All-season tyres are not as good in summer as summer tyres and not as good in winter as winter tyres, but have the advantage of being suitable for use all year round.