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).
Recommendation on tyre fitment for the 40/50 HP model, advising on standard and alternative tyres and warning against high-speed wobbles.
| Identifier | ExFiles\Box 53\3\ Scan073 | |
| Date | 17th October 1927 | |
| X4565 To Hm.{Capt. W. Hallam - Head Repairs} from Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}7/LG17.10.27. TYRES. X4565 X987 We recommend that the following information should be forwarded to all Depots :- The 6.75" semi balloon tyre which is at present standard on the 40/50 HP. is the only balloon tyre which we recommend for fitting on this car. We do not recommend a 6" medium pressure tyre which fits on the same rim. If smaller section medium tyres are fitted on well base rims, there will be a danger of high speed wobbles occurring on the front axle. A case has come to our notice. An alternative tyre which is not as good as the 6.75" Dunlop, but is passable, is the 6.2" Michelin tyre which fits on the same rims. This tyre is considerably larger in section than the 6" Dunlop. Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} | ||