If you take any bus, then on its sidewall can find the whole deposit of numbers, letters, icons and symbols. Of course it is clear that the marking of tires had something to do with their size and characteristics. But how?
Let's start with the simplest - sizes of tires. This is the main criterion for their consumer choices. Almost always close to the brand and model tire is written something like 195 / 65 R 15. It is this labeling indicates the size of the tire. Stands it is quite simple.
Latin letter "R" indicates a tire design. In this case - radial. The next one digit (15) - the size of the mounting rim tires. It is denoted in inches and should be the same size drives your car. The first three-digit number (195) - the width of the tire.
For normal operation it is necessary that the width of the tire tread was not more than 30 percent greater than the width of the drive on which it is mounted. The next figure (65) - the ratio of the profile height to its width. The higher the number, the tire is more "high".
Considered normal values ??range from 60 to 80. Tires with a lower value are called low-profile, but with a higher - high profile. Typically, the range of acceptable for your car tire sizes mentioned in his statement.
Tire size directly affect their performance. Contact patch with the road is directly connected with wide tires, and manageability - with a height profile. In the first approximation can be called with wide tires and low height profile of sport.
In this case, they are often much worse than the comfortable features and they are much less opposed to injury. On the contrary, with high profile tires are generally comfortable and better resist such things as hitting the curb, ride on a dirt, etc. In this case, in proportion to suffer, and manageability.
The following important characteristics of the tires - the so-called "index rate" and "load index". They can find on the sidewall of the tire in the form of one or two letters and two-digit number next to them.
Latin letter indicates the speed category, ie, at that maximum speed is rated, this model bus. Marking is carried out in alphabetical order, beginning with the letter I in steps of 10 km / h. T - speed index. This conditional parameter determines the maximum allowable vehicle speed is allowed by using the data bus.
