How to determine the tire load index in the markingcar wheels? Having seen an unfamiliar tire for a car, at first glance understand what this product is - the task is not easy. In reality, everything is much simpler than it seems at first sight. For this, there is a generally recognized marking, according to which to each character, the symbol on the lateral surface of the tire corresponds to a predetermined value, which determines the area of its use.
The entire tire marking system, although it isis quite clear and simple, it is not the subject of this article, but some points will be considered in more detail and carefully. In particular, the tire load index characterizes the load capacity of the product, i.e., the weight it can withstand. This index is located on the lateral surface of the tire after the size (for example, 170 / 60R16) and represents a two-digit number.
Each value that has a load indextires, there corresponds a certain load that the product can withstand. The larger the value of the index, the greater the load the wheel can withstand. So, the indicator 82 corresponds to a load of 475 kg, and the index 100 - to a load of 800 kg. There are special tables in which the corresponding values are given: the index of load-carrying capacity of tires (as otherwise called the tire load index) and the maximum permissible load for it in kilograms.
It would seem that everything is simple.We take the value of the permissible load on the index, multiply it by 4 and get the weight of the car with the load that this tire can withstand, or rather, the permissible weight for such tires. But this is wrong, it can not be done. The fact is that the tables give the maximum permissible load values, which corresponds to the load index of the tires. And if you calculate the allowable load by the above method, you get the limit value of the allowable load. And no product can not be operated under extreme conditions. Therefore, with such an estimate, it is necessary to reduce the permissible load by 20% when using a tire on a passenger car, and by 30% when used on an off-road vehicle.
It's not all the limitations by definitionpermissible load on the bus. There is such a thing - "weight" of the car. It implies how the load is distributed across the axles of the vehicle. For example, 30% of the load of a laden car falls on the front axle, 70% - on the rear axle. It is rather difficult to take into account the "weight distribution", such data is usually not published.
And one should also take into account such a factor -the higher the tire load index, the thicker the product and the greater its safety margin. So, the elasticity of such a tire is less, and the possibility of depreciation, compensation of road irregularities is worse. All the jolts and bumps from unevenness, pits and bumps will be more transferred to the body of the car, which will make the trip less comfortable and will cause additional wear of the suspension.
Another no less important parameter that you need isuse when selecting a bus, is the speed index. It is applied near the load index and is usually denoted by a Latin letter. As an example: J means that this tire can be used at speeds up to 100 km / h, and the designation P - use at a speed of one hundred and sixty km / h. Designations consisting of two letters, usually refer to tires designed for a speed of more than two hundred kilometers per hour. Needless to say, the speed of the car should not even come close to the permissible value of that set for this type of tire.
Here are the two indicators in the labeling, the indexspeed and load of tires, allow to evaluate the possibility of using this product on the car, taking into account your individual needs and driving techniques. And it is best to follow the vehicle's passport, in which the manufacturer indicates the types of tires that can be used.
