What do the tire speed rating codes represent?
3 Answers
Tire speed rating codes are introduced as follows: 1. a1 to a8 represent 5 to 40 kilometers per hour, b represents 50 kilometers per hour, c represents 60 kilometers per hour, d represents 65 kilometers per hour, e represents 70 kilometers per hour, f represents 80 kilometers per hour, g is 90 kilometers per hour. 2. j is 100 kilometers per hour, k is 110 kilometers per hour, l is 120 kilometers per hour, m is 130 kilometers per hour, n is 140 kilometers per hour, p is 150 kilometers per hour. 3. q is 160 kilometers per hour, r is 170 kilometers per hour.
The speed rating code on tires is a lowercase or uppercase letter indicating the maximum safe speed the tire can withstand. Having driven for many years and changed numerous tires, I always pay special attention to this marking when selecting new ones. For example, S stands for 180 km/h, H for 210, V for 240, and higher-end tires may reach W or Y, exceeding 270. These letters are typically marked on the tire sidewall, combined with other numbers like 195/65R15 91V, where V represents the speed rating. If the speed rating doesn't match the vehicle's recommended level, high-speed driving can cause overheating, deformation, or even blowouts. I recommend that car owners regularly check tire wear and choose a speed rating that suits their driving habits if they frequently drive on highways. For general family cars, V or H is usually sufficient, but performance cars require higher ratings to avoid significant safety risks.
Car enthusiasts find tire speed ratings particularly fascinating. That tiny letter, like T for 190 km/h, H for 210, V for 240, or Z and above for 260 km/h, directly impacts high-speed handling and stability. Since I usually drive fast, I prioritize V or W-rated tires when choosing, ensuring they won't slip or overheat during aggressive driving. These codes are established based on international standards, tested for performance in extreme conditions. Paired with load indexes—like 91 representing a 615 kg capacity—they provide a comprehensive assessment of tire performance. Exceeding limits during high-speed driving accelerates tire wear and may even cause loss of control. Always check your vehicle manual for recommendations, then consider actual usage. Before long trips, verify both tire pressure and rating compatibility.
