Tire balancing is the process by which imperfections and inconsistencies in the construction of tires are detected, computed and compensated for, so as to increase the life of the tires and deliver a smooth and comfortable ride. There are two basic types of balancing: static balancing and dynamic tire balancing. There are three separate types of dynamic tire balancing. These are using the high speed spin balancer method, the on-the-car high speed method and a recent innovation, tire balancing beads.
All tires must undergo a static balancing. This is where the tire is paced upon a spindle. This spindle is calibrated to indicate direction and amount of imbalance. If this measurement is within tolerances, the tire is shipped to the tire shop.
The tire and wheel assembly is mounted to a balanced axle and spun up to freeway speeds. The machine computes the amount and positioning of any conditions of imbalance in the tire and wheel assembly. The tire technician then affixes the proper size weights in the correct locations to correct this imbalance.
This kind of high speed balancing in the hands of a well-trained technician used to be the most accurate form of dynamic tire balancing. It takes into account any variations in the actual lug center of the wheel versus the hub center of the wheel. This kind of dynamic tire balancing is not seen very much anymore because the high speed spin balancer is safer to operate, since balancer heads were prone to failure and flying off at high speeds.
This is a relatively new technology, wherein the balance is not only dynamic, but continuous. This method of tire balancing has the tire shop or tire owner inserting weighted beads inside the tire itself. This mass of beads moves around inside the tire as the vehicle drives down the road, continuously correcting for imperfections in the tire.