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).
Personal opinion on tyre types and pressures for the 20 HP and Phantom models.
| Identifier | ExFiles\Box 14\4\ Scan004 | |
| Date | 17th November 1925 guessed | |
| contd :- -2- Personally I am using balloons on the 20 HP. and ordinary tyres at 40 lbs. pressure on the Phantom, and, going as fast as the roads will allow, any harder tyres feel like solids to me. R.{Sir Henry Royce} | ||