Tire Speed Ratings - What You Should Know

Since the invention of the automobile, many drivers have been concerned with one thing - speed. Understanding how fast your vehicle can go will help you have a more enjoyable and safer driving experience. But, to get a full understanding of how fast your vehicle can drive, you must have a firm understanding of tire speed ratings.

Many casual drivers do not even know that every tire is rated to travel at a maximum speed. This tire speed rating is printed on the rim of each tire that you have ever purchased, and you may have never noticed it.

Tire manufacturers put their products through strenuous testing, including speed testing. Depending on the intended use of a tire, a manufacturer will ensure that it can be safely used up to and appropriate top speed. They perform this test by spinning the tire against a weighted metal drum that represents the weight of a vehicle.

What Do You Need To Know About Tire Speed Ratings?

Understanding tire speed ratings is simple, and if you ever change the cheap tires on a vehicle you should pay close attention to them. The speed rating is usually marked after the tire size, which is printed in the rubber around the rim of each tire.

Let's take, for example the most popular tire size used in the year 2008 - P225/60R16. On your tire these numbers would be followed by a two digit number and a letter - 87R, for example. The 87 it denotes the tires load index or the amount of weight that it can safely carry. The R denotes the tire's speed rating.

The speed rating of a tire is usually represented by a letter L through Z. These numbers correspond to a maximum speed. For instance, L refers to a maximum speed of 85 mph or 120 km/hr. Y refers to a maximum speed of 186 mph or 300 km/hr. Here is a table with some of the most common tire speed ratings

L - 75mph or 120km/hr
M - 81 130
N - 87 140
P - 94 150
Q - 100 160
R - 106 170
S - 112 180
T - 118 190
U - 124 200
H - 130 210
V - 149 240
W - 168 270
Y - 186 300

It is important that you match your tire's speed rating to your vehicle. Most manufacturers recommend that you choose a tire that is at least one great higher the maximum speed of your vehicle.

Can You Downgrade To A Lower Speed Rating?

Choosing a tire that has a lower speed rating than that which is recommended is not a good idea. First of all, it is a big safety hazard. If for any reason your car accelerates to its maximum speed, a lower rated tire may fail. It may cause a blowout and an accident.

On top of this, many automobile insurance providers will not provide money for an accident if a vehicle is using an incorrect tire speed. Unless you plan on equipping a downgraded tire on your own, you will probably have some trouble finding a garage that will put them on for you as many mechanics will refuse to do so.

What Do You Need In A Tire As Far As Speed?

Most drivers do not need to worry about using higher rated tire speeds. For the most part, you need to have a tire that is capable of reaching a speed higher than your vehicle's maximum speed. This will ensure that you never cause a tire to go faster than it is rated for.

Some of the most common tire speed ratings are R - 106 mph, S - 112 mph, and T - 118mph. If you drive a sports car, you may find it necessary to purchase tire ratings like V - 149 mph or even Z, which denotes a tire capable of driving more than 149 mph.

Do not neglect to pay attention to your tire speed ratings. When you're searching for new tires, always keep technical specifications at the front of your head.

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