They lessen the immediate, dangerous effects of a blowout, essentially buying the driver a grace period. The development of run-flat tires is essentially a way to intervene between a relatively normal occurrence - a blowout - and its potential consequences - a minor inconvenience at best, a fatal crash at worst. Think about a huge yoga ball that's lost a little bit of air - it doesn't bounce or roll smoothly, and can't support your weight as well as one that's properly filled. If the air pressure is incorrect, it forces the other two factors to compromise, which weakens the entire tire and makes it more susceptible to damage. A tire's capacity is determined by the amount of air it's designed to hold in a chamber around the wheel, the strength of the air chamber and the rest of the tire's structure and the air pressure that's actually in the tire. These dramatic and dangerous events are more likely to occur when a tire with a previously unnoticed slow leak (and resulting low tire pressure) suffers some sort of puncture damage or simply can't bear any more load. If that air is able to escape, the entire purpose is defeated.Ĭontrary to popular belief, most blowouts aren't the direct result of a puncture on a previously pristine tire. This distinction is important to understanding how tires really work - they impose shape and structure on the air contained within. As the tire experts at Tire Rack explain, it's the air inside the tire that bears the weight of our car, not the tire itself.

Tires arguably take more of a beating than any other part of the car.

A regular car and driver can get by with a simpler design. Though pro drivers only need to make it back to the pit crew, the conditions on the track make the stakes pretty high. The public version of run-flat tires is not quite as complicated, but they don't need to be. Goodyear has been manufacturing tires like this since 1966. NASCAR run-flats are designed with multiple air chambers and liners - if the tire is punctured and an air chamber fails, another air chamber takes over the space to maintain contact with the road and prevent the catastrophic loss of control that would otherwise result from a high-speed blowout.

What is a run flat tire