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).
Recommended tyre sizes for the 40/50 HP chassis and policy for customer requests.
| Identifier | ExFiles\Box 81\1\ scan0079 | |
| Date | 9th September 1919 guessed | |
| COPY. To R.{Sir Henry Royce} from Bn.{W.O. Bentley / Mr Barrington} Copy to CJ. C. WP. X3044 Bn{W.O. Bentley / Mr Barrington}4/W28819. RE TYRE SIZES FOR PRESENT 40/50 H.P. CHASSIS. You will remember that we are adopting as standard 895 by 150 for the rear wheels and 895 by 135 for the front wheels. I think this arose from a Conference held in London. I have been asked several times exactly how this policy should be interpreted and have indicated that these tyre sizes are our recommendation but that we should not raise serious objection if customers desire to use 895 by 150 tyres all round, since some owners will no doubt object to carrying two kinds of spares, and prefer the one size for simplicity. I have pointed out that we do not recommend the use of 895 by 135 all round. We recommend the use of different sizes front and back because we believe the steering is a little better with these light tyres and also heavy tyres on the front are perhaps a needless expense. WP. (Paris) now writes in WP14/SB{Mr Bull/Mr Bannister}26819, copy of which I attach, pointing out that it is almost certain that some owners at least will run for considerable distances with odd tyres on the rear wheels, throwing additional duty on the differential. I do not think we should object to odd tyres being used on the rear wheels in emergency, but we ought to be strongly against owners making a practice of this. Do you not think that we should only recommend odd tyres front and back in those cases in which the customer is prepared to carry two types of spares, and that we would prefer him to use large tyres all round rather than risk continuous running with odd tyres on the back? I do not think this recommendation for different tyres front and back could be put forward very strongly and must be left entirely to the discretion of Sales and our Depots with some such guidance as above. Will you please inform me if you are in agreement with the above outline? Bn.{W.O. Bentley / Mr Barrington} | ||