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).
Comparison of weights and dimensions for low-pressure tyres from manufacturers India, Goodyear, and Dunlop.
| Identifier | ExFiles\Box 30\5\ Scan050 | |
| Date | 22th March 1935 | |
| 56a Cont......2. W.A. Robotham, Esq. 22nd March, 1935. The comparitive weights of different makers of real low pressure tyres are as follows:- Size. Plies. Weight. India. Goodyear. Dunlop. 6.00-16 4 21.03 21.25 22.50 6.00-16 6 24.41 - 29.06 6.25-16 4 - x 22.00 23.87 6.50-16 4 23.79 22.00 24.00 6.50-16 6 27.38 - 32.00 7.00-16 4 - x 27.44 27.25 7.00-16 6 30.64 - 36.00 x. Not made at present. You will see from the above that the weight of the India 4 ply 6.00-16 is slightly lighter than the Dunlop or Goodyear and that the 6 ply India 6.50-16 is a little heavier than Goodyear but a little lighter than the Dunlop. If you should be interested in the 6.25-16 tyre, we should be quite prepared to make it for you although it is not such a popular size as either the 6.00-16 or 6.50-16 tyres. We estimate that the figures for the 6.25-16 tyre would be as follows:- Rim. O.D. Cross sect. Cross Sect. Eff. Rad. Weight. Infl. inflated. underload. 4.00 28.80 6.49 7.15 13.31 4 ply-22.40 lbs. 6 ply-25.90 lbs. - Continued - | ||