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).
Axle shaft failures in Bentley chassis 65-HM & 71-BN, attributing the cause to poor driving habits.
| Identifier | ExFiles\Box 89\4\ scan0148 | |
| Date | 12th August 1937 | |
| 261 Hd{Mr Hayward/Mr Huddy}/SB.{Mr Bull/Mr Bannister} from Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls} Rm{William Robotham - Chief Engineer}/Gry{Shadwell Grylls}2/R.12.8.37. BENTLEY CHASSIS 65-HM{Capt. W. Hallam - Head Repairs} & 71-BN.{W.O. Bentley / Mr Barrington} 65.HM.{Capt. W. Hallam - Head Repairs} The failure in the rear axle of this car was due to a torsional failure of the offside axle shaft at the splined end. 71.BN.{W.O. Bentley / Mr Barrington} We do not know the mileage of this car, but from the chassis number, we presume it is very considerable. The offside axle shaft has broken, and the nearside twisted to such an extent that it would not last much longer. We believe that failures of axle shafts are due entirely to bad driving. Customers who break axle shafts probably either indulge in flat out get-a-ways in first gear, or never bother to have the engine revs. correct when letting in the clutch after a synchromesh gear change. This is borne out by the fact that some shafts are twisted off in a forward direction, and others in an over-run direction. We have endeavoured in the experimental department to reproduce failures of axle shafts and wheel drivers by very brutal driving. We were able to twist the shafts, but not even crack the wheel drivers at a time when the test had to be stopped due to failure of other parts of the axle which have never failed on experimental or customers cars. We have discussed this matter with By.{R.W. Bailey - Chief Engineer} who agrees with the views stated above. We do not know whether it is customary, but are of the opinion that whenever an axle shaft fails in a car, the other one should also be changed. Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls} | ||