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 in Hispano and RR cars.
| Identifier | WestWitteringFiles\N\July1925-September1925\ Scan227 | |
| Date | 1st September 1925 | |
| R.R. 493A (50 H) (D.D. 31, 12-6-25) J.H.D. ORIGINAL EXPERIMENTAL REPORT. Expl. No. REF: Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}2/1/811. 9.25. C To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to CJ. BJ. c. to RG.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} c. to DA.{Bernard Day - Chassis Design} EY. c. to Wor.{Arthur Wormald - General Works Manager} HIGH SPEED STEERING WOBBLES. [Handwritten: Test 74214] We have carried out further tests with the Hispano car. The conditions were exactly similar to those of our last report with the exception that the wings were removed so that we could observe the wobbles. We should say that the Hispano is not as bad for high speed wobbles as the Phantom. We find that the wobbles build up rapidly and die away rapidly. We could get no prolonged continuous wobble with a reasonable amount of out of balance. The actual nature of the wobbles on [strikethrough]this[/strikethrough] car are exactly similar to those we have previously observed of the front axle taking up a criss cross vibration. We have run a RR. car with 5º forward lean on the pivots. In this condition the steering was somewhat unstable but not actually dangerous. We found that if we fitted the largest section balloon tyres, it would even self-centre. We noticed a marked improvement in high speed wobbles with this forward lean. We can still get high speed wobbles with our largest section balloon tyres but these would not build up. We are confirming these tests on another car. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||