What are Run Flat Tyres?
Most premium and mid-range tyre brands have standard and run-flat versions of the different tyres they manufacture. As such, it is wise to check what is fitted to your vehicle before making a purchase.
Look for this icon when buying tyres to show which ones are run-flat tyres.
Run-flat tyres are specially designed to enable them to operate for a specified speed and distance in the absence of any inflation pressure.
Run-flat tyres most commonly achieve this through reinforced sidewalls, shown in yellow in this diagram.
Without any inflation pressure, a standard tyre collapses, making the vehicle undrivable.
Whereas the reinforced sidewalls of the run-flat tyre can support the vehicle's load, maintaining a drivable ride height at reduced speed and distance.
A typical run-flat tyre can be driven without any tyre pressure, known as 'flat tyre running mode', at 50 mph for 50 miles in the event of a puncture.
Certain run-flat tyres, known as extended mobility tyres (EMTs), provide run-flat capabilities over a shorter distance, which is generally 50 mph for 20 miles.
What are the Benefits of a Run Flat Tyre?
Run-flat tyres' distance and speed capabilities can vary slightly across tyre or vehicle manufacturers. As such, it is critical to refer to your vehicle handbook and the tyre's sidewall for specific Run-flat capabilities.
The purpose of run-flat tyre technology is to maintain mobility for the driver, enabling them to drive to a tyre repair centre, where the tyre can be repaired or replaced, according to the manufacturer's guidelines.
Having run-flat tyres fitted does not mean a tyre can be driven for multiple journeys, so long as the overall ditance capability is not exceeded. Acting this way would risk the driver's and other road users' safety.
Run-flat tyres differ across tyre brands, with different names, tyre marking to denote they are run-flat tyres and tyre repair criteria.
For more information about how to recognise run-flat tyres and which run-flat tyres can be repaired, visit our advice page; what are run-flat tyres?