How do run flat tyres work?

Run flat tyres are designed to allow motorists to keep control of their vehicle and continue driving when they experience a puncture. The distance you can safely travel following a puncture to a run flat tyre can vary depending on the tyre manufacturer and various other factors including the number of people travelling in the vehicle. It is best to check you owner’s handbook for accurate ‘run on flat’ distances.

Run flat tyres are built with reinforced sidewalls which temporarily hold up the weight of the vehicle even after a puncture, allowing valuable time to take the vehicle to a suitable place to repair or replace the tyre. As they are designed to minimise the difference in drive quality when a puncture occurs, run flat tyres are fitted with Tyre Pressure Monitoring Systems (TPMS) to alert drivers to a puncture or change in pressure.

When regular tyres are punctured the driver will often experience loss of control of the vehicle. This occurs when the sidewall of the tyre, which is usually kept secure against the rim by the internal air pressure, becomes separated from the rim flange and drops into the well of the wheel. As soon as the beads are disconnected from the rim flange, loss of steering control will occur. The difference with run flat tyres is that they are designed to keep the tyre beads securely anchored to the rim flange area of the wheel even when operating at zero pressure. This allows drivers to keep control of their vehicle and continue driving for around 50 miles.

Driving on a punctured run flat tyre

Most run flat tyre manufacturers advise that it is safe to drive on a punctured run flat tyre for around 50 miles at a reduced speed of up to 50mph. However, this does vary so it is advisable to check your owner’s manual. The longer that you drive on a punctured run flat tyre, the more stress you put on it, reducing the possibility of a puncture repair. It is therefore advisable to get your tyre assessed as soon as possible after experiencing a puncture.

Changing from run flat to conventional tyres

Although it is possible to change from run flat to conventional tyres, we would not advise doing so without speaking to the vehicle’s manufacturer. When a vehicle is designed to be fitted with run flat tyres as standard, in order to improve the ride quality, the suspension system is tuned to incorporate them into the design. Changing the tyres back to conventional tyres could therefore have an adverse effect on the car’s handling and performance.

To purchase run flat tyres for your vehicle simply enter your tyre size into the search tool at the top of the page. Our search allows you to filter your results to display only run flat tyres. You can also call our National Sales Team on 0800 028 9000.