It seems common sense to keep an eye on your tyres, but many of us are guilty of running classic cars with tyres that are past their best. Defences that 'I only use the car a few times a year and only in dry weather,' or 'I don't drive it hard' are irrelevant: Her Majesty's Coroner for Manchester wrote to the Federation of British Historic Vehicles recently to implore classic car owners not to use ancient tyres on their cars, after the death of an MGB owner.

The MGB in question seems to have been a concours contestant, that had been fitted with a set of 'as-new' wheels and tyres bought at an autojumble to give the perfect authentic finish. Though hardly used, the tyres were 25 years old. While driving at a modest speed, the driver experienced a 'wheel wobble' - after a short time, the tyre burst, the car spun, clipped a kerb and flipped over, killing the driver and injuring the passenger.

This tragic incident must call into question the extremes to which concours competitors go to achieve perfect originality. Tyre rubber deteriorates with age - not just light - and old tyres can be highly dangerous. I learnt this myself a few years back - my father has always kept his Morris Minor Traveller on crossplies and I was delighted to find a pair of new, unused original Dunlops on eBay. They were still in their original wrappings, which meant they had not been exposed to UV rays, which I thought was the only concern with old tyres. Unwrapped and on the car, they looked great - until we drove on them. Crazing appeared within a few miles and I sadly advised my father to take them off. Only a few months ago, I learned that he hadn't - when he admitted that one of them had suddenly deflated, fortunately at very low speed. He was very lucky.

It is suggested that the reasonable life expectancy of a tyre is 10 years - and a tyre that's been sitting on the shelf for more than six years should not be put into service. This is because tyre compounds deteriorate with age - some more than others.

I think it's fair to say that the best makes, like Michelin, last better than cheaper ones and that conditions of storage do make a difference; my 1960 Super Two has two Michelin ZX tyres on that must be at least 20 years old, but they show no signs of crazing and stand up to hard driving without a flinch. But I do accept that I'm taking a risk by driving on them and I think I'd better replace them soon. It's a pain in the wallet, especially for little-used cars, but that's better than risking a horrendous accident.
Malcolm McKay, Motorbase News Editor