Kiirusindeks

Kiirusindeks, also known as the speed rating or speed index, is a designation found on tires that indicates the maximum speed at which a tire is safely rated to perform. This rating is crucial for vehicle safety, particularly at higher speeds. The speed index is represented by a letter, with each letter corresponding to a specific maximum speed in kilometers per hour (km/h) or miles per hour (mph). For example, an 'H' speed rating indicates a maximum speed of 210 km/h (130 mph), while a 'Y' rating signifies a maximum speed of 300 km/h (186 mph).

Tire manufacturers determine these speed ratings based on rigorous testing that assesses the tire's ability to withstand centrifugal forces, heat buildup, and structural integrity at various speeds. It is important for vehicle owners to select tires with a speed rating that meets or exceeds the maximum speed capability of their vehicle. Exceeding a tire's speed rating can lead to overheating, tire failure, and a loss of control, posing a significant safety risk.

The speed index is typically found on the sidewall of the tire, usually located near the tire size designation. While often overlooked by consumers, understanding and adhering to the speed rating is a vital aspect of tire maintenance and safe driving practices. Always consult your vehicle's owner's manual for recommended tire specifications, including the appropriate speed rating.