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).
Tyre and suspension choices for the 40/50 and 20 HP models to prevent wheel wobble.
| Identifier | ExFiles\Box 67a\1\ scan0107 | |
| Date | 25th March 1926 | |
| To R.{Sir Henry Royce} from CJ. CJ2/E25/3/26 - 2 - or balloons on the back wheels of the 20. As regards the front wheels of the 40/50, Hs.{Lord Ernest Hives - Chair}'s recommendation is that on no consideration should these be fitted until we are in a position at the same time to fit the hydraulic shock absorber. His reason is that he is confident that wobbles are set up more easily and frequently if the medium pressure tyres are used instead of the standard tyres. Your remedy, namely, that the maximum speed should be reduced does not appear to be within the region of practical politics; if you meant that we should reduce the power of the engine, this would undoubtedly affect our sales but, what is worse, it would affect our reputation because it would be clear that we should be doing so in order to avoid wobbles. I for one certainly would not agree to any reduction in speed, nor would I, in the face of Hs{Lord Ernest Hives - Chair}'s repeated warnings, agree to the fitting of medium pressure tyres on the front wheels of the 40/50 until we can fit the hydraulic shock absorber. BJ is entirely of the same opinion. I have already explained that we regard wobbles as something very terrible and something which is likely to affect our reputation and sales most seriously and, therefore, something which must at all costs be avoided. I think, if the opinion of the Sales Conference were taken on this matter, they would all agree with what I have said here. As regards the 20 HP, the conference at Derby yesterday agreed that the medium pressure well base rim tyre might be standardised immediately for the 20 on all four wheels and there is no objection to the larger diameter balloon tyre on the back wheels. We next come to your suggestion that we should supply both on the 40/50 and on the 20 tyres for the back wheel of a different from the tyre for the front wheel. You will remember that far back in the history of motoring this was found to be extremely inconvenient because of having to carry two sizes of spare tyres and all makers strove to overcome this inconvenience and did so by having the same size tyres on the front wheels as on the back. | ||