Tyres and rim sizes
By H. Kishie Singh

A LADY told me a strange tale. They were on the highway and had a puncture. The car ran for quite a distance before the puncture was discovered. This is quite common with radial tyres. They deflate very slowly, so slowly that one can drive many kilometres before realising that the tyre is flat. By that time, the tube and tyre, and even the rim, can get damaged.

And that’s exactly what happened to this lady. By the time she came to a stop, the tube was in tatters, irreparably damaged.

She changed into the spare wheel. (Make sure the spare wheel is properly inflated. It can be required any time.)

The car was road worthy and the lady was soon on her way. However, there was a long journey ahead of her so at the first town she decided to have the punctured tyre repaired. A very wise move. If you have had one puncture, a second one can also happen.

The rim and tyre were in serviceable condition, only a tube was required.This simple drill, however, became a major exercise. No tube was available for her make of car. Finally, a wise man solved the problem saying that ‘‘Agar Santro ki tube nahin hai, toh Zen ki dal do!’’

Horror!

Tubes and tyres are made by manufacturers who supply to the car manufacturer. You cannot buy a tyre or tube in the car manufacturer’s name. It will be available in the tyre manufacturer’s name and will be termed Original Equipment (O.E.) for that particular car. And this tyre will have a rim size, always in inches. It is never advisable to change the rim size on a vehicle. The manufacturer has designed the entire suspension and steering around the rim and tyre size.

The tyre size is like your shoe. It can’t change — or should not change. Some youngsters like to fit oversized tyres and rims onto their cars. It does nothing to improve the performance of the vehicle. On the contrary it could adversely affects the handling of the car. It will definitely affect fuel consumption. So stick to the manufacturer’s recommendations. The tube should be compatible with the tyre manufacturer’s brand name. Try not to use a Dunlop tube in a Bridgestone tyre. Mind you it will work. But a marriage of the same brand names will do far better. The match would be a perfect! Caste system in tyres and tubes definitely exists. Inter-marriages should be avoided!

The chart here gives the tyre size according to the rim as specified by the manufacturer.

Some tyres available in the market (alphabetically) Bridgestone, Ceat, Dunlop, Falken, Goodyear, JK, MRF.

Happy Motoring!

This feature was published on October 2, 1999