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 and tyre testing.
| Identifier | ExFiles\Box 68\1\ scan0111 | |
| Date | 1st October 1925 | |
| R.R. 493A (50 H) (D.D. 31, 12-8-25) J.H.D. EXPERIMENTAL REPORT. Expl. No. +8450 REF: Hs{Lord Ernest Hives - Chair}/Bm1/LGS.10.25 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 EA. BY.{R.W. Bailey - Chief Engineer} c. to Wor.{Arthur Wormald - General Works Manager} +457 HIGH SPEED STEERING WOBBLES. Mr. Healey of the Dunlop Rubber Co. paid a visit to the Works last Thursday (Oct.1st.) and we went overhigh speed steering wobbles. He brought with him three types of tyre :- (1) A normal straight sided cord tyre with the tread ground to a ridge. (2) A normal straight sided cord tyre with the tread ground as flat as possible. (3) A tyre of normal dimensions externally but having the layers of cord at a different angle to that normally employed, this construction strengthening the lateral stability of the tyre. The tests comparing the relative merits of these tyres were somewhat masked owing to the fact that none of the tyres were very true when running on the drums - those with the tread ground flat being especially bad in this respect. The general results shewed, however, that the amplitude of the wobbles was considerably reduced by the flat tread tyre. This has since been confirmed on the road. We could detect absolutely no difference between the standard tyre and the one having the cords arranged for lateral stability. We have asked Messrs. Dunlop to provide us with some tyres that run truly and are ground to the shapes previously mentioned that we may repeat the tests and get more accurate comparisons. contd :- | ||