Get The Skinny On Your Spare
Sydney Morning Herald
Friday April 30, 2004
Space-saver spare tyres have come in for heavy criticism yet again following safety tests measuring their effects on handling and braking. Carried out by engineers from the Royal Automobile Club of Victoria, the tests showed vehicles using the skinny spares had reduced cornering grip and longer braking distances.
In one vehicle not fitted with anti-lock brakes, the braking distance from 80kmh to a halt increased by 15.4 metres, or more than three car lengths.
"Keeping control of a vehicle under emergency braking and swerving was also increasingly difficult," says the RACV's chief engineer, Michael Case. "The wheel continually locked without [electronic anti-lock braking] when attempting to stop quickly, causing the vehicle to pull to one side, and leaving significant flat spots on the tyre."
When a space-saver tyre was fitted to the rear, particularly on a 4WD, cornering grip decreased by at least 13 per cent. Case says space-savers first appeared in space-starved sports cars, but were now standard on "anything from small sedans to roomy 4WDs".
Following the tests, on four vehicle types in emergency braking, cornering traction and swerving, the RACV called for:
n Car makers to fit full-size spare wheels in new vehicles where space permits and to provide prominent, comprehensive warnings about the safe operation of vehicles with space-savers.
n Dealers to inform buyers that a vehicle has a space-saver.
n Replacement space-savers to be made readily available, as with other spare parts.
"The public is in the dark about these tyres," Case says. "Many people don't even know their car has one until they have a flat. If [motorists] are not happy ... they should insist on a full-sized replacement wherever possible."
© 2004 Sydney Morning Herald
Share This