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).
Tests conducted to understand and mitigate high-speed steering wobbles.
| Identifier | WestWitteringFiles\N\July1925-September1925\ Scan312 | |
| Date | 12th June 1925 | |
| R.R. 493A (50 H) (D.D. 31, 12-6-25) J.H.D. EXPERIMENTAL REPORT. To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c. to CJ. EJ. 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} Expl. No. ORIGINAL. HIGH SPEED STEERING WOBBLES. 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. With [strikethrough text] 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, is that 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 steering and an axle held rigidly in torsion would be preferable. from the contd 4 Handwritten notes: Top right corner: C Next to title: Y457 / 78420 | ||