What does the tyre speed index say?

off-road tires

What does the tyre speed index say?

The last abbreviation of a full tire designation, seen on the sidewall of the tire, designates the tire’s speed index. It is a measure of the maximum speed at which the tire can be operated. A total of 32 speed classes are defined. However, the tire index stands for more than just the permissible maximum speed. A high index also means better traction and braking power.

Which tire index fits which vehicle?
The tires of a motor vehicle must at least correspond to the specified maximum speed of the vehicle or a higher speed class. The vehicle registration document (registration certificate) provides information under point 15.1 (front wheels) and 15.2 (rear wheels) about which of 32 different classes the tires should have according to the manufacturer. This is a recommendation that can be deviated from if the recommended tire index allows a significantly higher speed than the vehicle can achieve. This is often the case, for example, when a car model is available with different engines.

What should be considered for the speed index of cars registered before May 1st, 2009?
For vehicles registered before May 1st, 2009 , a small safety margin must be added to the stated maximum speed of the vehicle. In the case of vehicles registered after May 1, 2009 , however, the maximum speed specified in the vehicle registration document is decisive. The speed index H (up to 210 km/h) is therefore sufficient for cars whose maximum speed is specified in the vehicle registration document as 208 km/h, even if the letter V (up to 240 km/h) or W (up to 270 km/h) is in the vehicle registration document ) is specified. If in doubt, a specialist dealer can help you with the selection.

READ MORE:  A Guide to right Tire Air Pressure

Does the prescribed speed index also apply to winter and all-season tires?
Exceptions apply to winter tires and all-season tires . The Road Traffic Licensing Regulations (StVZO) allow winter tires to have a lower speed index than that required for summer tires. For example, if V tires (up to 240 km/h) are prescribed for the vehicle, the fitted winter tires may belong to tire class R (up to 170 km/h) or T (up to 190 km/h). However, a sticker or sign showing the maximum permissible speed of the tires must be visibly attached to the windscreen.

Which speed index for tires applies abroad?
In many European countries , the regulations on the speed index are similar to those in Germany. In Switzerland , for example, the speed index of the tires must at least cover the maximum speed specified in the operating manual. This also applies regardless of the fact that vehicles in Switzerland are generally not allowed to drive faster than 120 km/h on motorways. Winter tires for passenger cars must have at least the index Q (up to 160 km/h).

What to look out for with the tire index in Italy
During the summer months (May 16th to October 14th) in Italy only tires with a speed index that corresponds at least to the points 15.1 and 15.2 in the vehicle registration document may be driven. This also applies to winter and all-season tires. If, for example, the speed index H (up to 210 km/h) is required according to the registration certificate, part 1, any winter tires that may still be fitted must also correspond to this speed index.

READ MORE:  What you should pay attention to when buying tyres?

Share this post


READ MORE:  A Guide to right Tire Air Pressure