MOTOR AND CYCLE.

Taranaki Daily News, 26 August 1920, Page 6

MOTOR AND CYCLE.

SYNTHETIC RUBBER. German chemists boasted that they had succeeded during the war in producing a satisfactory rubber. At a recent general meeting of German rubber factories at Leverkusen, however, it was admitted that synthetic rubber could not compete with the real article, either in price or quality, and all the synthetic rubber factories have therefore been closed. TYRE WEAR. Although a basic fact, it is not usually realised that tyre wear represents approximately one-third of the running costs of a car. In other words, every time a four-gallon tin of fuel, costing approximately ISs, is fed into the tank, the sum of 6s should be placed on one side to repay for the wear that will be caused to the tyres during the time that fuel is used in propelling the car. Every motorist has at some time or other experienced trouble with tyres, and it is trouble of such a nature as to make him desire to leave them well alone when they are apparently in order. Therefore these expensive accessories become neglected, and by reason of that neglect deteriorate much more quickly than they should. Therefore, they need replacing more often than should really be necessary, and the running costs of a car are not kept so low as they might be. First and foremost, the life of a tyre depends mainly upon the degree of inflation. The non-technical owner is apt to connect any article made of rubber with the term elasticity. He argues that because rubber is flexible, it is the business of a rubber tyre to flex and absorb the inequalities of the road, and he sub-consciously thinks that because his covers are flexible they are working under proper conditions when they bend and spread out considerably on passing over a stone or projection. In point of actual fact, this is far from being a correct assumption. The duty of a tyre is to absorb very minor road shocks. It is meant to act as a cushion, and not as a spring. Withiri limits, the less a tyre flexes, the longer will it last.