How Run-Flat Tires Work

A Dash of Caveats
Even though there are many great advantages to a self-supporting run-flat tire, there are certain caveats to remember when considering or operating them. While run-flat tires are capable of working without the assistance of internal air pressure, there are some restrictions. Should a run-flat tire deflate, Bridgestone recommends a top speed of 50 mph, and a maximum safe distance of 50 miles.


Another important consideration deals with how well the self-supporting run-flat tire works. As the tire loses air, the sidewall structure inside the tire begins to support the entire weight of the vehicle. While a rapid tire blowout may be easily noticed in a run-flat tire, a gradual loss of tire pressure may not be noticed at all by the driver. Since this could potentially force operation of a run-flat tire beyond its safe limits, a pressure monitoring system is highly recommended. It is for this reason auto manufacturers are restricting the installations of run-flat tires only to cars equipped with this feature. In the event that a tire begins losing air, a dashboard warning light on vehicles equipped with tire pressure monitoring systems alerts drivers of the problem. Self-sealing tires work differently than run-flat tires and do not require such a pressure monitoring system. The additions of these small safety measures are a welcome trade for a new technology that won't leave you feeling flat.