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).
Comparison of the diameters of Dunlop cord beaded and straight-sided tyres and the negligible effect on gear ratio.
| Identifier | ExFiles\Box 49\2\ Scan052 | |
| Date | 27th January 1922 | |
| C. from Hs. {Lord Ernest Hives - Chair} c. to BY. {R.W. Bailey - Chief Engineer} c. to EP. {G. Eric Platford - Chief Quality Engineer} X4299 Hs {Lord Ernest Hives - Chair} 2/LG27.1.22. DUNLOP STRAIGHT-SIDED TYRES. X4050 X4299 At your request we have measured the difference in diameter between a 695 X 130 Dunlop cord beaded tyre and a 33 X 5 Dunlop straight-sided tyre. We find that the Dunlop beaded tyre measures 34 5/8 dia. - the straight sided tyre in a similar condition measures 34 1/8 dia. This slight difference in diameter would be negligible on the gear ratio. It would be swallowSWALLOWed {J. L. Edwards} up by the differences in tyre pressure or the wear of the tyres. Hs. {Lord Ernest Hives - Chair} | ||