How to Distinguish Run-Flat Tires?
2 Answers
Run-flat tires can be distinguished by: 1. Checking the sidewall specifications, which will have special symbols that regular tires do not have; 2. Placing the tire flat on the ground and standing on it—the sidewall of a run-flat tire will be hard, while a regular tire will feel soft when pressed by hand. Run-flat tires are designed to prevent the vehicle from losing control in the event of sudden tire pressure loss. They consist of an outer tire, a standard inner tube, a spare inner tube, a steel rim, a gas generator, a pressure sensor, and a control unit. Characteristics of run-flat tires include: 1. They provide support and resilience, allowing the wheel rim and tire to work together to support the vehicle safely in case of sudden air loss or a blowout; 2. After a blowout, run-flat tires do not lose air immediately, enabling the driver to continue driving for a certain distance with reduced pressure; 3. Run-flat tires have reinforced sidewalls, enhancing their durability and usability.
When I usually repair cars, I often help people distinguish between run-flat tires and regular tires. The main thing is to look at the markings on the tire. Run-flat tires will have RF (Run-Flat), RFT, or ZP (Zero Pressure) printed on the sidewall, commonly seen on brands like Michelin or Bridgestone. Also, feel the sidewall—it's thicker and much stiffer, hardly deforming when pressed, whereas regular tires are soft and pliable. In use, run-flat tires can last about 80 kilometers after a puncture to reach a repair shop, with the dashboard warning light on, while regular tires will completely fail upon a blowout. Price-wise, run-flat tires are significantly more expensive, roughly 30%-50% higher, and require professional equipment for installation to avoid damaging the rims. It's advisable to check these features before changing tires to ensure rim compatibility, otherwise, it could affect driving safety.
