How do the letters on tires represent speed ratings?
2 Answers
Tire speed ratings can be divided into different grades from A to Z. The further back the letter representing the tire speed rating is in the alphabet, the better the tire performance. Below is a detailed introduction to tire parameters: 1. The load index is a number corresponding to the maximum load capacity (unit: kilograms), indicating the maximum weight the tire can bear under normal inflation conditions. 2. The speed rating is an indicator letter ranging from J to Z. Under the corresponding load capacity of the relevant load index, each letter represents the maximum speed the tire is allowed to reach. These two factors together are referred to as the service description and are interdependent with the load index. For example: In the tire specification 195/65R15-91V, the load index is 91, corresponding to a maximum load capacity of 615 kilograms, and the speed rating is V, meaning the maximum speed is limited to 240 km/h.
The letters on tires represent speed ratings, like a speed ID card for a car. The system is standardized, with letters ranging from L to Y, each corresponding to a specific safe speed. For example, T stands for 190 km/h, H for 210 km/h, and V can go up to 240 km/h. I can see it on the tire sidewall, like in the code 205/55R16 91V, where V is the speed letter. This standard is based on international safety tests, ensuring the tire performs stably at high speeds without overheating, deforming, or blowing out. When choosing, it must match the vehicle's requirements—if the rating is too low, driving on highways becomes risky and may shorten the tire's lifespan. I usually check this letter when inspecting tire pressure to remind myself that safe driving is the top priority.
