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).
Experimental tyre tests concerning high-speed wobbles, comfort, noise, and skidding.
| Identifier | ExFiles\Box 29\1\ Scan212 | |
| Date | 25th March 1926 | |
| To G.J. from Hs.{Lord Ernest Hives - Chair} c. to B.J. x457 Hs{Lord Ernest Hives - Chair}1/LG25.3.26 X1583 x457 X4565 Referring to the telephone message which we have received from you today. From experimental tests, the oversize medium tyres on the front will increase the tendency for high speed wobbles. There will be no increase in comfort with the medium pressure tyres if they are run at pressures to reduce wobbles. The hydraulic dampers will eliminate high speed wobbles with medium pressure or semi balloon tyres. As soon as the hydraulic dampers are available, we should push the standardisation for 21" rims and well base tyres. The semi balloon tyres are no more prone to punctures than the tyres we use at present. As regards skidding, these tyres are fitted with a new pattern tread which makes them an improvement in this respect. This new pattern tread has the disadvantage that it xxxx increases the amount of noise caused by the tyres. It is for this reason that Sales have already condemned these tyres. Dunlops have agreed that they will make up tyres to suit us, retaining the same tread as they use on the present tyres. This will mean that we shall have the same amount of noise as at present but we shall not have the advantage of the less tendency to skid which is a feature on the new tread. Our opinion is that it would be unwise to rush into standardising the medium pressure or semi balloon tyres. Our recent tests which have been carried out in contd :- | ||