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).
Proposed changes to wheel and tyre sizes to improve steering, with a comparison table.
| Identifier | ExFiles\Box 90a\3\ Scan066 | |
| Date | 11th June 1935 guessed | |
| Steering as regards lightness. Have you got any 19 inch wheels at the works or shall I order some from Rudge Whitworth. I will order a set of new Rudge hub nuts. Hope you have brought back some news of the unsupercharged Bugys entered for the T.T. Kind regards, Yours Sincerely, T.P.M.H. The fronts we propose to use 5.25 x 19 instead of 6.00 x 18, the narrower treads will help the steering + they are only .15 less than the 6.00 x 18 overall diameter. I will give you the comparative sizes of the tyres we used last year + the tyres we propose for this year. size Diam Effective Rad Rears LAST YEAR 6.00x18 30.75 14.90 THIS YEAR 6.00x19 31.30 15.35 Fronts LAST YEAR 6.00x18 (Standard) THIS YEAR 5.25x19 30.60 15.10 The 5.25x19 has a tread of 5.80 whereas the 600x18 has a tread of 6.40 which would not help the | ||