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).
Comparing the performance of rubber studded Dunlop Magnum tyres against all-rubber tyres on greasy roads.
| Identifier | ExFiles\Box 81\1\ scan0152 | |
| Date | 17th December 1918 | |
| R.R. 235A (500 T) (S.D. 408. 26-4-17.) Bm. 2/156/13. X.990 EH9/LG17.12.18. 17th December 1918. To R.{Sir Henry Royce} from EH. c. to CJ. c. to E.{Mr Elliott - Chief Engineer} RE 49- GB. X.2631. X.682. X.990. On the run back from West WitteringHenry Royce's home town to Derby we noticed how remarkably well 49 GB stuck to the road. There is no doubt that the new rubber studded Dunlop Magnum tyres are most effective as regards preventing side slipping on greasy roads. There was very little difference in the condition of the roads when we went on 7 CA to when we returned on 49 GB but whereas with 7 CA fitted with studded tyres fitted diagonally the car was skidding about the whole time, with 49 GB we never had a single side slip. We know under most other conditions the all-rubber tyre is distinctly nicer than the studded one. In future we should always recommend Dunlop Magnum tyres be used on a car. Although they will undoubtedly lose their efficiency as wear, the same thing applies to the studded tyre. EH. | ||