What does 91W on a car tire mean?

1 Answers
McRosalie
07/29/25 5:54pm
91W tires refer to tires that can bear a load of 615kg and support a maximum speed of 270km/h. The following is about the tire speed rating codes: According to the different maximum speeds they can support, tire speed ratings can be divided into different grades from A to Z, with grade A further subdivided into eight different levels from A1 to A8. Generally speaking, the further back the letter representing the tire speed rating is, the better the tire performance. Common speed ratings mainly range from Q (160km/h) to Y (300km/h), and tires with different speed ratings have different applicable ranges: 1. Q-T grade tires (maximum speed 160-190km/h) are suitable for small and compact cars. 2. U-V grade tires (maximum speed 200-240km/h) are suitable for mid-to-high-end cars. 3. W-Z grade tires (maximum speed 240-300km/h) have better performance and are therefore more commonly used in large luxury cars and supercars.
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