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).
Fitment of 6-inch tyres on the 20 HP car, detailing objections and recommendations.
| Identifier | ExFiles\Box 58\1\ Scan010 | |
| Date | 19th November 1926 | |
| X5820 To FN. from Hs.{Lord Ernest Hives - Chair} c. to BJ. c. to Sg.{Arthur F. Sidgreaves - MD} Hs{Lord Ernest Hives - Chair}1/LG19.11.26 20 HP. TYRES. X5820 / X4565 With reference to PN{Mr Northey}5/EH18.11.26. There is no fundamental reason why 6" tyres cannot be fitted on the 20 HP. car. The 6" tyres will fit on the same rims and that are now standard on the 20 HP. for the 5 1/4" tyres. The objections to the 6" tyre are, that they reduce the steering lock, and make slight alterations to the wing clearance etc. If 6" tyres are fitted, we recommend the pressures in the front tyres are not reduced below 35 lbs/sq.in. This will ensure that the steering is not too heavy. The rear tyres can be run with a low pressure if desired. We have no fear of high speed wobbles on the 20 HP. car with 6" tyres. Hs.{Lord Ernest Hives - Chair} | ||