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).
Advantages of low tyre pressures and a strategy to convince tyre manufacturers.
| Identifier | ExFiles\Box 39\2\ Scan099 | |
| Date | 13th October 1921 | |
| X3538 W/S Sp.{Mr Spinney} from Hs.{Lord Ernest Hives - Chair} Hsl/LG13.10.21. TYRE PRESSURES. X3538 X4050 We are convinced that high tyre pressures, not only spoil the riding of a 40/50 H.P. car, but less mileage is obtained before the tread is worn through. As we believe only a small majority of our customers have tyres retreated, this means that the tyre is scrapped. We are anxious to send to all Rolls-Royce Owners a pamphlet recommending that they should use low type pressures. Before we do this, however, we want, if possible, to get the agreement of the tyre manufacturers. We attach herewith copies of letters we have sent to the Dunlop Company and the Goodyear Company. We believe that we can convince the Dunlop people. We have arranged to go over to Birmingham and interview them in regard to this matter. We suggest it would be a great help if you would take the matter up with the Michelin people. You would get far more satisfaction by going to see them than us writing from here. We are running a set of Cable Michelin Tyres on the Experimental Car weighing 45 cwts. with a tyre pressure of 50 lbs. The line of argument we take up with the tyre maker is - why should the tyre pressures be high. Their usual reply is that the pressure is required to be kept high to prevent the casing of the tyre flexing excessively and causing it to burst. They might also say the high tyre pressures improve the efficiency of the car. Our reply to contd:- | ||