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).
The discontinuation of 6.75' Traction Tread tyres by Dunlop and issues with the new replacement triple stud pattern.
| Identifier | WestWitteringFiles\P\2July1926-September1926\ Scan194 | |
| Date | 21th September 1926 | |
| To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c. to BJ. Wor.{Arthur Wormald - General Works Manager} c. to E.{Mr Elliott - Chief Engineer} Da.{Bernard Day - Chassis Design} c. to Ev.{Ivan Evernden - coachwork} ORIGINAL Hs{Lord Ernest Hives - Chair}/Rnl/T21.9.26. 40/50. 6.75" TYRES. X4565 X46050 In spite of the fact that the 6.75" Traction Tread Tyres which we have been running in France are still being distributed by the Dunlop Paris Depot, they are no longer being made by the English Co. All the moulds have been converted to the triple stud pattern in accordance with the Dunlop Co.'s decision to adopt this type of tread. We have a number of objections to the triple stud covers, most of which we enumerated to their development Dept. in March (Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}15.3.26). The most serious objection at the moment is that any tread which is a better "non-skid" than the traction pattern is likely to be worse for high speed wobbles. The triple stud is definitely designed to prevent skidding. It is therefore necessary to conduct further tests to ascertain that the 6.75" tyre has not been spoilt for our purpose by the substitution of the triple stud tread. However, the Dunlop Co. yielding to pressure from other people as well as ourselves, have modified their original pattern to increase wear and decrease noisiness. Incidentally we believe from a cursory examination of the tread they have removed some of its anti-skidding properties. Unfortunately none of the 6.75" tyres will be available with this modified pattern for approx. one month. The present triple stud is hardly worthy of serious consideration because | ||