New tyre time

Press, 10 June 1977, Page 9

New tyre time

The beginning of winter is the best time to fit new tyres, according to Dunlop. Tests in Britain have shown that new tyres wear most quickly in summer when road temperatures are highest. Dunlop recommends that new tyres, particularly radial-ply tyres, be “run in” at low speeds during winter when roads are cold and wet and maximum grip is needed for safety. New tyres, because of their deeper tread, provide this grip by pumping the road surface dry.

Driving at no more than 80 km/h for 80 km is usually enough to “run in” new tyres.

A new tyre has a deep tread, which, because of the greater volume of rubber, means that heat can build up in the tread itself

and the tyre casing, making the tyre wear more. Most radials provide greater mileage than cross-plies and there are also benefits to fuel economy. More than 50 per cent of new car tyres sold in New Zealand are now of radial construction

However, if any new tyre is run in on hot roads the rate at which it wears increases as temperatures rise. A cold or wet road surface has the opposite effect, cutting down heat build-up because road and a : - temperatures are cooler. Wet roads add to the cooling effect on the tyre. New tyres run in carefully during winter will normally give greater mileage and radials have the added advantage cf giving better grip in slippery winter conditions, providing extra safety.