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).
Results of testing three different tyre sizes to understand their effect on high-speed wobble.
| Identifier | ExFiles\Box 29\1\ Scan248 | |
| Date | 10th September 1926 | |
| To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c. to BJ. Wor.{Arthur Wormald - General Works Manager} c. to RG.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} c. to DA.{Bernard Day - Chassis Design} BY.{R.W. Bailey - Chief Engineer} X457 Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}1/LG10.9.26. HIGH SPEED WOBBLES. X457 X4050 X4565 With reference to our Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}5/T23.8.26. in connection with peripheral weight tending to reduce the susceptibility of a tyre to high speed wobble. It is rather interesting to note that we have been testing three sizes of tyres in France (all of 6-ply construction) These are - 6" Dunlop, 6.2" Michelin, and 6.75" Dunlops, all of which fit the same size of wheel. The 6.75" tyres wobble the least, the 6.2" are intermediate, the 6.00" are the worst. We are trying to conduct a test to substantiate this theory more fully. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||