One of the jobs I do for the MSCC is to act as Federation of British Historic Vehicle Clubs liaison offier see www.fbhvc.co.uk

I have reproduced below the text of the two articles from the FBHVC on this subject I have published within the MSCC.

Check your tyres

And by that, it doesn't just mean checking the tyre pressures and making sure there is enough tread, but making sure the side walls are in good condition and the tyres not unduly old. An accident took place last year in which the driver of an H registered MGB lost his life when a rear tyre burst on the M56. Evidence shows that the driver was a skilled mechanic and a careful and experienced driver who was not travelling particularly fast at the time. The car was described by police as being maintained in an excellent condition. The surviving passenger said that just before the accident the driver had commented that a "tyre wobble" had developed and he was going to "drive through it". The wobble went briefly, but then the tyre burst, causing the car to spin, clip a kerb and flip over. Subsequent investigation showed that - although hardly used - the tyre was 25 years old. It was one of a set of as new tyres and wheels purchased at an autojumble.

Tyres – again!

In the last liaison report I mentioned the tragic circumstances that had caused an MGB owner to loose his life due to using tyres that were too old. More details have emerged of the technical issues surrounding use of old tyres. Car tyres are made from a synthetic styrenebutadiene rubber which is easy to manufacture and has a significantly lower cost than natural rubber, but it does have the disadvantage that it is more prone to oxidisation. To counter this, tyre compounds contain anti-aging additives. Unfortunately, these chemicals are harmful to human health and the amounts are strictly controlled at a level that is a compromise between tyres lasting a reasonable time and minimising health risk. The ‘reasonable time’ is around ten years. If a tyre has been standing around unused, oxidisation means a stiffening of the tyre walls so that when it is next used the unaccustomed flexing will cause heat to build. The natural degradation of the compound increases rapidly causing the long molecular chains that give the compound its flexible properties to shorten, and ultimately causing the tyre to start to break up. The tyre failure on the MGB was consistent with this.


Phil Egginton
1979 4/4 4 seater