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).
From 'R' to 'CJ' discussing the shift in preference from 3-speed to 4-speed gearboxes for the 20 HP and 40/50 HP models.
| Identifier | ExFiles\Box 6\4\ 04-page154 | |
| Date | 19th October 1925 | |
| To CJ. from R.{Sir Henry Royce} X5310 R4/M19.10.25. My dear CJ. (As. for your information. CJ.) EXPERIMENTAL WORK. X. 8310 X. 5310 X. 8920 Referring to your CJ7/E16.10.25., and the mention of a 3-speed gearbox, we had no idea of using one. It was pressed by me when coachbuilders rushed for central change, where 4-speed control is inconveniently clumsy. Also weight, cost, and low geared back axles, made we think that 4-speeds were an unnecessary complication. It is now agreed that buyers prefer the 4 speed box, and in the 20 HP. we have overcome some of the objections of bulk, and weight and hope to apply this type soon to the 40/50 HP. Yours ever, R.{Sir Henry Royce} | ||