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).
Secret memorandum discussing issues and potential improvements for the car's springing and suspension system.
| Identifier | ExFiles\Box 72\3\ scan0035 | |
| Date | 19th July 1924 | |
| X.9410 To BJ. from R.{Sir Henry Royce} c. to CJ. Wor.{Arthur Wormald - General Works Manager} Rg.{Mr Rowledge} BY.{R.W. Bailey - Chief Engineer} DA.{Bernard Day - Chassis Design} E.{Mr Elliott - Chief Engineer} HS.{Lord Ernest Hives - Chair} S E C R E T. R1/M19.7.24. E.{Mr Elliott - Chief Engineer} A.{Mr Adams} C. RE. R-R SPRINGING. X.9410. The beauty and success of the RR. springing was due to the following :- The front of the car had about the usual clearance bump. This is inadequate for very supple springing. This was necessary for other reasons, chiefly steering and with the shock dampers that have always been fitted to this end of the car, the front was always very steady. The back axle in pre war days, as at present, had ample clearance and a large bump and very supple and frictionless springs. For ideal riding at slow speeds on reasonable roads this was satisfactory, but had the front of the car been sprung in the same way the whole car would have pitched from the front to the back like a ship with a heavy head sea. After the war owing to the change in the construction of the tyres and the makers instructing them to be hard pumped, it was found absolutely necessary to considerably increase the damping of the rear axle, which was done by thin leaf springs with considerable 'nip' between the plates, and with additional shock dampers. This condition reduces the beauty of riding unless it is done with moderation, and the tyres are kept at low pressures. In the car which created the bad impression the rear springs were much stiffer than in your car, but more than this, there has been a change in the springs independent of instructions, in which there appears to be considerably more internal friction, and enormously more than the thick leaf springs which PN.{Mr Northey} favours. I feel certain therefore that the passengers, especially those in the rear seats would not, and could not, detect the difference in the 25% increase of stiffness in the front of the car, and it has a tendency to steady the front of the car, and so make it possible that the rear springs, as pointed out by E.{Mr Elliott - Chief Engineer} could be probably still more supple. Passengers in the usual closed body would say that the car with the slightly more rigid front springs, and the slightly more supple rear springs rode even better than our present standard practice. In conclusion, I am very anxious that we shall not be driven into some complicated method of construction, through being obsessed with the information and specimens which were submitted to you. Naturally I have great sympathy in your criticisms, which were extremely just, but I fear the reason for the dissatisfaction was wrong. R.{Sir Henry Royce} | ||