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).
Engine vibration periods on 20/25 HP cars when fitted with Bentley flywheels.
| Identifier | ExFiles\Box 103\1\ scan0157 | |
| Date | 6th February 1935 | |
| To By.{R.W. Bailey - Chief Engineer} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c. to MX.{John H Maddocks - Chief Proving Officer} X5300 Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}15/KW.6.2.35. 20/25 HP. Flywheels. Confirming our conversation with you, we have now had some half dozen 20/25 cars through test with the Bentley flywheel fitted to them, and find that they bring up a slight engine period round about 2,200 r.p.m. This period is not sufficiently serious to stop production, but we think it is undesirable if it can be avoided. It can be eliminated by reverting to the original 20/25 flywheel. We understand, however, that 400 forgings for the lightened flywheels have been produced for the G.{Mr Griffiths - Chief Accountant / Mr Gnapp} and H.{Arthur M. Hanbury - Head Complaints} series, and these will not make the heavy type. All that we ask at the moment is that before more forgings are ordered we shall be allowed to say whether they should be of the heavy or light type. We presume that the heavy type dies are still in existence. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||