Non-standard spare wheels

Tyres for emergency use only

Tyres on the same axle must be of the same size and aspect ratioof your hand are the only parts of the car in touch with the road

Tyres on the same axle must be of the same size and aspect ratio

You must always make sure that tyres on the same axle are of the same size and aspect ratio - your car will fail the MOT test if they're not - but the law makes an exception for temporary use spare wheels fitted in an emergency.

Temporary use spare wheels - non-standard spare/skinny spare - are increasingly being supplied as standard by car manufacturers to save space and weight. Generally these will be narrower than the standard size car tyres.

You can find details of any operating restrictions in the handbook, and the spare tyre itself should be clearly marked too. Maximum speed is usually restricted to 50mph for safety reasons.

Space-saver wheels are designed for temporary use to enable the vehicle to be driven to a place of repair. There is no maximum distance but due to the speed restriction, limited tread depth (only 3mm from new) and the fact that the tyre compound is often softer to simulate the traction capabilities of a wider tyre, the distance covered before repair should not be excessive.

Aim to get the original car tyre repaired or replaced as soon as possible.

Buying a new car

If you are buying a new car check the specification to find out if a 'normal' or non-standard spare will be supplied as standard equipment. Some car manufacturers give the option to upgrade a skinny spare to a standard-size spare, while others don't supply a spare wheel at all and fit run-flat tyres or supply an emergency sealant and inflator pack instead.

Handling will be different with a skinny spare fitted. Allow for this when driving as well as following any specific advice printed in the handbook.

Caravans/trailers

If you are towing a caravan or trailer and get a puncture then it is generally OK for a space-saver spare to be fitted to any axle on the car. check the handbook though as there might be vehicle-specific advice.

With the skinny-spare fitted you must drive straight to a tyre specialist for a repair/replacement rather than attempt a long journey.

(25 April 2012)