Tire itself is software, the tire profile supports the tire drum shaped, a central hub is installed on the shaft parts is called hub.

The same diameter, but the width is not the same, there is the opposite, but the data are different from the two wheels, suitable for their own different tires. Some people think that the original tire is not high enough, to upgrade, is often a widening, reducing the ratio of flat, increase the diameter, change the material, this time, if you have to change the wheel, called modified hub.

Car wheel hub bearings in the past most of the use of single row tapered roller or ball bearings. With the development of technology, the car has been widely used car wheel hub unit. The use range and usage of the hub bearing unit are increasing. The third generation has been developed. The first generation is composed of double row angular contact bearing. The second generation of the outer roller path is used to fix the bearing flange, and the bearing sleeve can be simply fixed on the axle. Makes the car's maintenance easier. The third generation hub bearing unit is adopted for the bearing unit and the anti lock brake system. The hub unit is designed to have inner and outer flanges, and the inner flange is fixed on the drive shaft, and the outer flange is arranged in the bearing.