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).
Factors affecting the riding comfort of the Phantom II, including tyre pressures, spring bedding, and load distribution.
| Identifier | ExFiles\Box 65\2\ scan0303 | |
| Date | 1st January 1930 | |
| To Ps. (Paris). From Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} X7820 HS{Lord Ernest Hives - Chair}/Rn.{Mr Robinson}2/MJ.1.1.30. X.7770 X.7410 X.7820 PHANTOM 11 RIDING. We have now had a fair amount of experience with Phantom 11 riding. We are sorry it was not possible for us to come across to Paris to investigate the car of which you complained but the next 10,000 miles car will be in France at the begin-ning of February with one or two members of the Expl. Dept., when you will be able to obtain any assistance you require. Briefly, we have established that comfort at very low speeds is largely controlled by the tyre pressures. We have recommended, for anyone who is using their car continually in town, that the front tyre should be run at 35 lbs/sq.in. and the rear at 30 lbs/sq.in. It is surprising what a difference five sq. ins. increase over these figures makes to the very low speed riding comfort. The other factor which contributes to low speed riding comfort is the spring bedding. At present we are not sure what it is worth but we are taking steps to get consistency in this direction. The Depot Sheet for altering shock absorber loading is now in circulation but we do not think that you will find shock absorber loading to be the predominating factor in your particular trouble. We should like to add further that a full petrol tank effects a material improvement in rear seat riding with only one passenger at the back. If we can tell you anything further we shall be glad to do so, but we should like to impress upon you that the semi-eliptic springs alone have not conferred perfect riding on Phantom 11. It is only when advantage is taken of the construc-tion to build a car like 18-EX with two spare wheels at the rear, that the best results are obtained. HS{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} | ||