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).
Investigations into high-speed steering wobbles.
| Identifier | ExFiles\Box 29\1\ Scan086 | |
| Date | 29th September 1925 | |
| R.R. 498a (50 H) (D.D. 31. 12-6-25) J.H.D. EXPERIMENTAL REPORT. Expl. No. +457 REF. Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}1/LG29. 9. 25 To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/R m.{Mr Moon / Mr Moore} 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. X457 We have been carrying out careful investigations to determine the exact effect of castoring angle on a standard Phantom axle and pivots. These tests were conducted on the dynamometer drums. The wheels were toed in a quarter of an inch at the front. We find that we can obtain wobbles with a forward pivot lean of 4°. There is a steady decrease in the violence of the wobbles as we go forward with the pivots starting at 4° backward lean. This improvement is only slight however. When we go from 4° forward to 6° forward, there is a very marked improvement, and beyond this we were unable to produce high speed wobbles. We know that with 6° forward lean, road tests show that all self-centering has not disappeared owing to the trans-verse inclination of the steering pivot. At the first opportunity we are trying a standard axle with vertical pivots which is at present being made. We have, in addition, been running a car without a side steering tube. We find that although we arranged the car so that we got violent wobbles when the side steering tube is coupled up - when it is disconnected we cannot get wobbles to build up. contd :- | ||