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).
High-speed steering wobbles caused by out-of-balance Rapson tyres versus Dunlop tyres.
| Identifier | ExFiles\Box 39\1\ Scan171 | |
| Date | 9th January 1925 | |
| W/S. H.{Arthur M. Hanbury - Head Complaints} from Hs.{Lord Ernest Hives - Chair} X1288 Hs{Lord Ernest Hives - Chair}3/LG9.1.25. HIGH SPEED STEERING WOBBLES. X1238 J457 With reference to your H2/TB2.1.25. Our reply to CJ's question is that we have run over 100,000 miles in France on cars fitted with 4-wheel brakes with Dunlop tyres, also with Rapson tyres fitted. It was reported that the Rapson tyres brought up oscillations on the steering wheel. There was no complaint when fitted with the Dunlop tyres. The cars were driven as fast as any 40/50 HP. will go. In view of this we do not think it would be of much value to run a car on Brooklands. At the present time the Brooklands Track is closed unless a very special permission is obtained. Our complaint with Rapson tyres fitted to The Prince of Wales car was that the tyres were out-of-balance. Our limit for a wheel and tyre being out-of-balance is 2 to 3 ozs. on the rim diameter. The wheels fitted with Rapson tyres on The Prince of Wales car were 12 to 14 ozs. Any tyre, whether Rapson, Dunlop or any other make would be condemned by us as being unsuitable for RR. cars when they are that amount out-of-balance. We find the Dunlop tyres keep within our limits of out-of-balance. The steering wobbles which were complained of contd :- | ||