What Do the Letters on Tires Represent in Terms of Speed?

[LaKathryn]

Tire letters represent speed ratings as follows: 1. Q stands for 160 kilometers per hour; 2. R stands for 170 kilometers per hour; 3. S stands for 180 kilometers per hour; 4. T stands for 190 kilometers per hour; 5. H stands for 210 kilometers per hour; 6. V stands for 240 kilometers per hour; 7. W stands for 270 kilometers per hour; 8. Y stands for 300 kilometers per hour; 9. Z or ZR indicates speeds above 240 kilometers per hour. Methods for maintaining car tires: 1. Regularly check tire pressure; 2. Remove debris from tire treads; 3. Inspect tire wear and replace them promptly as needed; 4. Perform tire rotation to ensure even wear across all four tires and prevent excessive wear.