What does the term speed rating mean in regard to a tire?
The term speed rating arises from the method used to test the structural integrity of tires. This is closely related to the amount of belting the tire has and the loads the tire can withstand, such as cornering and braking. Structural integrity of a tire design is tested by spinning them at increasing speed until centrifugal force tears them apart. Different speed ratings are assigned based on this data. Engineers design vehicle suspensions to load tires during braking, cornering and driving. If the vehicle is engineered for a specific rated tire and a lower rated tire is substituted, handling and safety can be effected. Problems can also appear with irregular wear and vibrations.
