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).
Letter from Dunlop comparing the weights of Magna Wire Wheels and Spoked Disc wheels.
| Identifier | ExFiles\Box 157\2\ scan0054 | |
| Date | 14th October 1936 | |
| HEP/BMT.795. SHEET NO. 2. 14th.October, 1936. (Dict. 13th). Messrs. Rolls-Royce Limited, DERBY. _ _ _ _ _ _ _ _ _ 4.50x16 Magna Wire Wheel ............... 23 3/4 lbs. This wheel is used on the Wolseley 25 Limousine. 4.50x16 Spoked Disc wheel - in replacement. 24 lbs. This particular wheel is used on the Wolseley 16, 21 and 25-HP Models. From the above figures I think it can be appreciated that, except in the case of the larger Wire wheel where big centres are employed, the adoption of the Spoked Disc wheel on similar cars brings about an increase in unsprung weight. It is, of course, apparent that in the case of 17" or 18" diameter comparisons of the heavy type of wheel - owing to the additional material in the Spoked Disc wheel as against the Wire wheel of spoked construction - the same weight advantage would not be obtained. Yours faithfully, FOR THE DUNLOP RUBBER CO.LTD. H.C. Price Manager, Car Manfrs. Division. | ||