From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Technical bulletin about the causes and solutions for high-speed steering wobbles.
| Identifier | ExFiles\Box 28\4\ Scan254 | |
| Date | 22th June 1925 | |
| To EP.{G. Eric Platford - Chief Quality Engineer} from Hs.{Lord Ernest Hives - Chair} c. to Wor.{Arthur Wormald - General Works Manager} C O P Y: HIGH SPEED STEERING WOBBLES+ We recommend that the following information is circulated to all Depots and Officials :- There have been complaints of wobbles in the steering at high speeds. This complaint is prevalent on a large number of modern cars. The reasons we can give, so far, for the complaint only becoming apparent on recent cars are :- (1) Introduction of front wheel brakes which has lowered one of the periods of the axle on the springs. (2) Introduction of low pressure tyres or using lower pressure in the standard tyres. Experience shows that the following points reduce the tendency for this high speed steering wobble to occur :- (a) Balance of wheels and tyres. Although this has always been necessary, it has become more vital than ever that the tyres and wheels should be in absolute balance. (b) Tyre pressures. It has been found that with increase in tyre pressure the wobbles have been put up to a higher speed. If attention is given to this point, it may be possible to put it up to such a speed that the car seldom reaches. (c) Extra friction on the front shock absorber will tend to reduce the steering wobbles. (d) Extra friction in the steering pivots will tend to reduce them. The above items are given in the relative order of importance. Hs.{Lord Ernest Hives - Chair} | ||