Tire parameters - interpretation

Each motorist should face need of interpretation of designations on tires sooner or later. In practice it is absolutely simple, important to remember the sequence of the described parameters only.

Interpretation of parameters of the tire

As a rule, designations on tires are printed in such format: 000/00 R00 00 A AB. At the same time:

1. The first three figures always designate tire width in millimeters.
2. The second two numbers are the relation of height of a profile to width as a percentage.
3. Letter R indicates actually a radial design of the tire (but not the radius or the size as many believe).
4. At once letter R is followed by two numbers indicating diameter of a disk in inches.
5. Two following numbers specify the maximum permissible level of load of a wheel (this information is especially relevant for minibuses and small-sized trucks).
6. The single letter – tire speed, than it is higher, those with greater speed can go by this tire.
7. Two letters at the very end of an inscription tell about additional characteristics of the tire.

Interpretation of an inscription on tires does not represent special complexity, but is very important for the correct selection of wheels.

Interpretation of wheel tires on an example

For descriptive reasons we will consider interpretation of dimension of tires on a concrete example. Let's take for consideration such parameters: 195/65 R15 91 T XL.

1. So, the first as it was already told above, prompts how many millimeters tire width is. In our example – 195 mm.
2. The second speaks about proportionality, or, in other words, a profile. In our case it is 65%. It is important to consider this indicator as its increase is in most cases inadmissible.
3. R is printed on all modern tires as all of them are issued with a radial cord.
4. Number 15 indicates diameter of a wheel in inches – the internal dimension of the tire or the external size of a disk.
5. In our example the index of loading is specified 91 (in the special table it is possible to see how many it in kilograms). For cars this parameter is little significant, and here owners of minibuses should pay attention to it.
6. The index of speed in our case of T, or 190 km/h.
7. Letters XL indicate that the tire is strengthened, capable to sustain big loading, than the tire without such marking.

Besides, there are also other additional designations.

Knowing how truly to decipher tire parameters, you do not make a mistake and will make really favorable and successful acquisition.

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