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).
Necessity of retaining the clutch brake on the Phantom II model despite the introduction of synchromesh.
| Identifier | ExFiles\Box 15\5\ Scan295 | |
| Date | 11th May 1932 | |
| Hs{Lord Ernest Hives - Chair} X7310. X7310 X7480. To E.{Mr Elliott - Chief Engineer} from Sg.{Arthur F. Sidgreaves - MD} Copy to Mr. Hs.{Lord Ernest Hives - Chair} PH. re Synchromesh, and the Clutch Brake. Sg{Arthur F. Sidgreaves - MD}/E11.5.32 Referring to E.1/HP.7.5.32, whilst it is correct that we have not used a clutch brake on the 20/25, it is something which we rather regret and I think we must be very, very careful before we do away with the clutch brake on the P.II. Whilst the introduction of synchromesh renders a clutch brake unnecessary on several gears, it still seems to be very necessary to enable one to engage a gear in the first place. PH made some tests specially with a P.II and found that the time required for bringing the clutch to rest while the engine was running at normal slow speed as in traffic with the clutch brake in operation was 1 1/2 seconds whereas with the clutch brake cut out of action, the time taken was 10 seconds. We should be running into a number of complaints if we turned out a car on which one had to wait a long time before being able to engage a gear from a standing start, and it would be quite hopeless and an undesirable condition, especially in these days of traffic stops, if we had to put up with any delay in bringing the clutch to rest greater than that which exists at the present time. Is it not possible that with synchromesh to arrange for the clutch brake to be operative from neutral to first or second and, say, from first to second, if, as I gather from your memo., that is the only other change when it would be of use. I think Mr. Hs.{Lord Ernest Hives - Chair} should conduct an experiment on one or two of his cars such as that referred to above and let us have his views. Sg.{Arthur F. Sidgreaves - MD} | ||