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).
Wheel rim sizes for 'SS' cars, comparing 20 inch and the standard 21 inch options.
| Identifier | ExFiles\Box 17\7\ Scan023 | |
| Date | 20th February 1929 | |
| To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to Sg.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager} c. to E.{Mr Elliott - Chief Engineer} DA.{Bernard Day - Chassis Design} c. to BY.{R.W. Bailey - Chief Engineer} X7810 Hs{Lord Ernest Hives - Chair}1/LG20.2.29. WHEELS FOR 'SS{S. Smith}' CARS. Y527 18-EX car is running in France fitted with wheels with 20" rims, 19-EX car is running with 21" rims which is the present standard. We have now come to the point when it is necessary to inform Dunlops what rims we require and it is proposed for the first batch of cars to order standard 21" rims. There is no reason, if the smaller wheel is desired either from a gear ratio or an appearance point of view, that it cannot be used because the tests on 18-EX shew that it was perfectly reliable and the tyre mileage was very good. Hs.{Lord Ernest Hives - Chair} | ||