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.
| Identifier | ExFiles\Box 29\1\ Scan081 | |
| Date | 26th September 1925 | |
| R.R. 493a (50 H) (D.D. 31. 12-6-25) J.H.D. EXPERIMENTAL REPORT. Expl. No. 4457 REF Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}3/LG26.9.25. To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c. to CJ. BJ. c. to RG.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} c. to DA.{Bernard Day - Chassis Design} BY.{R.W. Bailey - Chief Engineer} c. to Wor.{Arthur Wormald - General Works Manager} HIGH SPEED STEERING WOBBLES. 78430 We have carried out tests with hubs which enabled us to throw the front wheels 2" and 4" out of centre point steering respectively by increasing the front track. We ran these hubs with the worst wobble promoting 7.25" balloon tyres. We found that with 4" out of centre point we could get no high speed steering wobbles. With 2" out of centre point however, we could get mild wobbles. When we set the wheels parallel, and put a slight amount of damping on the front shock absorbers, these wobbles disappeared. We carried out further tests with the 2" out of centre point hubs to ascertain to what extent braking on one wheel would affect the steering! We found that when we applied one front brake only, the car had a tendency to move to the side in question but that this could be counteracted with one hand on the steering wheel. The main difference between this and the taking charge which we have previously experienced due to the front pivots assuming a forward lean, the less in the former case the more the car goes on the lock, the less the pull on the steering is felt, in the latter case the tendency to take charge increases with the lock. The front brakes we had on the car when this test was made, were not very efficient. We should say however that one brake in action with 2" out of centre point contd :- | ||