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).
Measurements and standards for wire wheels with well-base rims for 20 HP and 40/50 HP chassis.
| Identifier | ExFiles\Box 42\1\ Scan060 | |
| Date | 6th May 1926 | |
| c. to Hs.{Lord Ernest Hives - Chair} 43809 BY/G10/G.6.5.26. WIRE WHEELS WITH WELL-BASE RIMS. ----------------------------- With reference to Wd{Mr Wood/Mr Whitehead}6/NJ4.5.26, we have now been able to take measurements of the wire wheels with well-base rims, which have been supplied to us for testing out experimentally for our 20 HP. and 40/50 HP. chassis, and find that the centre lines of the tyres relative to the hub shells are approximately the same as our standard for wire wheels for straight sided tyres, although Messrs. Dunlops' blueprints S.68 and S.69 show the wheels built up with well-base rims to be offset by the amounts previously quoted. It is very important that we maintain what has always been our standard for the relative position of the centre line of the tyres with the hub shells, as we do not agree to using wheels with the amount of offset indicated by their blueprints referred to above. In regard to the spoking of wheels with well-base rims, we have examined those they have supplied to us for experimental purposes, as referred to in the first paragraph of this memo, and we notice that they have not maintained the same features which were adopted in conjunction with the Dunlop Co. for S/S. type of wheels viz. that each spoke is crossed by three others. We are about to standardise wire wheels with well-base rims for our 20 HP. chassis, therefore we consider that the Dunlop Co. should make arrangements to supply us with wheels in accordance with our requirements, and that they should supply revised blueprints showing the correct position of tyre centre line and the spoking. In regard to wire wheels with well-base rims for 40/50 HP. chassis, although, as pointed out above, those which they have supplied to us experimentally are arranged with the tyre centre lines approximately in our standard position, we notice that some wheels which they have supplied to us for customers orders for use on the rear axles have an offset as indicated on their blueprint S.69, but before we can adopt these they will have to be modified both in regard to the position of the tyre centre line and the method of spoking. BY/C. | ||