MOTOR TYRES

Rotorua Morning Post, Volume 2, Issue 302, 16 August 1932, Page 2

MOTOR TYRES

TREND TOWARD FTJRTHER INCREASE IN SIZE. It is difficult to foretell what sized pneumatic tyres will be used a few years hence. he sizes now standard throughout the world were the rational outcome of the wide swing from high-pressure tyres to medium balloons some eight or nine years ago. At that period it yas predicted that super-sized balloon tyres, ranging from 71 in,. to 9in. in diameter, were likely to hecome standard equipment. A few such tyres were made, but neither the automohile industry nor the public were ready for such outsizen tyres. The outcome was a general increase of about 25 per cent. in section sizes 'of the tyres then .i':andard by all leading makers. Even that increase necessitated appreciable alteration in car design, notably in steering and adoption of shock absorbers. During the last two years, owing to the increased speed capabilities of cars and the demand for the utmost in comfort, thene has been a trend toword increasing tyre section sizes, and already many cars and truclcs in New Zealand are running on tyres considerably larger than were used 011 similar vehicles a few years back . Low Pressure Tyres. Car and tyre manufacturers are not satisfied that the ultimate has yet been reached in respeet to low-pressure large-sectioned tyres, and the latest developments indicate a tendency to swing back to the abnormal sized balloon tyres which makers experimented with back in 1923-. Already replacement business in a small way is being done overseas with these outsized balloon tyres, which are inflated at pressures varying from 101b to 201b per square inch according to size and load. These large-sectioned tyres do not call for larger wheels, the increase in section being taken cars of by the use of very small rims, which range from I2in to 16in diameters, so that the disc wreels in appearance look mostly tyre. It is yet premature to forecast what will be evolved from the latest developments, but the new form of big balloon tyre has yet to prove itself a better all-round tyre proposition than those now standard before the world's leading automohile manufturers and tyre-makers will face the colossal outlay incidental to a radical change in wheel and tyre equipment. It has been computed that a sum exceeding £6,000,000 would be alone involved in the making of the new tyre moulds, etc. It is certain there can be no startling change in this direction and any development will be gradUal.