Although it may seem confusing to understand the Tyre speed rating basics, we will help you grasp everything. Note that the code you see on your tyre sidewall represents some information such as the width, diameter, height, rim size, tyre speed rating and load index rating another other. In most case, the last single letter of the tyre code indicates the tyre speed rating. Taking 204/56R/17/93V tyre code, for example, the letter V indicates the speed rating for that tyre.
What you should expect on this page.
- What is the meaning of Tyre speed rating?
- Whys is it very critical to know your tyre speed rating?
- Is it okay to fit your car with a higher/ lower speed rating tyre?
Tyre speed rating explained?
The speed rating of your tyre is the measure of the maximum speed that it can withstand when running at its appropriate load capacity. Each tyre has a particular speed rating indicated as a letter, and its main purpose is to ensure your tyre safety while driving at the maximum speed.
There are various speed rating ranging from L to (Y) with each representing certain kilometres. It is important to note that these abbreviations are founded based on European kilometres usage. These speed ratings are typically met when tyre engineers run tyre prototypes in a variation of ten-minute increments until the expected speed has been reached. Typically, the difference between each letter is about 6mph.
Tyre speed rating chart
- L = 120kmh/75mph
- M = 130kmh /81mph
- N = 140kmh 87mph
- P = 150kmh /93mph
- Q = 159kmh/99mph
- R = 170kmh /106mph
- S =180kmh /112mph
- T = 190kmh /118mph
- U = 200kmh /124mph
- H =210kmh /130mph
- V = 240kmh /149mph
- Z = +240kmh+/149mph
- W = 270kmh /168mph
- Y =300kmh /186mph
- (Y) = 300kmh+/186mph+
It is important to note that the speed rating ranging from V to (Y) are typically for sports cars with extremely high speed. Additional, the L rated tyres are mainly for light and off-road trucks with medium carrying capacity.
The Q tyre speed rating represents tyres mainly for winter 4x4s vehicles which are likely to encounter frost or muddy roads hence require additional friction. R is mainly for the heavy-duty and light trucks while S and T are particularly for vans and family saloons. U is primarily designed for couples and saloons while H is for both couples and sports saloons.
Remember that the diameter of the tyre is directly proportional to the speed rating. This means that the larger the diameter, the higher the speed rating since these tyres are mainly intended for purposes on higher-performance cars which ought to handle higher speed.
However, in most modern cars, there is a disparity in that the tyre rating is not always equal to the maximum speed the vehicle is capable of reaching. For instance, most modern family cars have their tyre speed rating higher than that of the cars maximum speed.
The main reason for this to ensure ultimate safety which therefore means that the ultimate tyre performance is set to exceed the maximum performance of your car. For this reason, even at maximum car speed, the tyre has an additional capacity to handle instant braking, acceleration as well as high-speed cornering.
Why is it important to know your speed ratings?
It is important to note that when driving your car at higher speed, the wheels usually turn very fast which results to the emission of heat due to friction between the tyre and the rough surface of the road. This means that the chosen tyres should have the capacity to cope with such heat even for long distances.
However, the speed rating isn’t only designed for handling speed but also help you enjoy a comfortable ride, minimizing tread wear, increasing cornering ability and also for traction. For instance, a tyre having a higher speed rating has better stopping power and also grip, although it may not perform optimally in winter or cold weather conditions. For this very reasons, tyre speed rating V, Z, W and Y are particularly suitable for higher-performance cars for warmer climates.
Can you fit your car with a tyre rating higher than the car speed rating?
Of course yes, it is because such tyre can perform optimally even when travelling at the maximum car speed. On the other hand, lower tyre speed rating than the car speed rating should be fitted since they have a higher chance of malfunction when the car exceeds this tyre speed rating.
Higher speed rated tyres tend to be constructed from higher strength materials in comparison to slower speed rated tyres and they tend to have extra reinforcement. Both these extra features allow such tyres to cope better under higher pressure and strain when driven at higher speeds.