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).
Adoption of straight-sided cord tyres for the 'Goshawk' model and their performance.
| Identifier | WestWitteringFiles\G\June1921\ Scan103 | |
| Date | 22th June 1921 | |
| To BY.{R.W. Bailey - Chief Engineer} from R.{Sir Henry Royce} c. to CJ. c. to BJ. c. to C. c. to PN.{Mr Northey} c. to Hs.{Lord Ernest Hives - Chair} c. to Da.{Bernard Day - Chassis Design} c. to R.R. Inc. for attention of OY. X3056 R9/G22.6.21. X.4050 X.3056. RE STRAIGHT SIDED CORD TYRES. I am very pleased to see from Mr. Hives report that the straight sided cord tyres are likely to be universal. We think we ought to start up the "Goshawk" with this type, and therefore the wheels and tyres for the experimental cars should be ordered of this pattern. It is agreed that the springing must be well damped with this class of tyre, but if it should lessen the cost of running cars it is a decided advantage. As far as my own tests are concerned, I have obtained very comfortable and economical running with the tyre pressure about that suggested by Mr. Hives. At the same time I obtained very good petrol consumption, namely, about 18 miles per gallon on our 40/50 H.P., just natural conditions and fairly high speed driving over 50/100 mile journeys. In cases of light bodies where the back wheels carry so much less weight, this matter of tyre pressure in the back wheels becomes increasingly important, especially on certain roads, bumpy, or pot-holey. R.{Sir Henry Royce} | ||