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 Industrial Rubber Products discussing Miller tire sizes and options for a customer's vehicle.
| Identifier | ExFiles\Box 53\1\ Scan007 | |
| Date | 16th February 1922 | |
| Telephone: Museum 4363, 4364. INDUSTRIAL RUBBER PRODUCTS. LIMITED. Miller Tires. Brook House, 191-192, Tottenham Court Road, LONDON, W. 1. S. R. {Sir Henry Royce} Chichester, Esq., Coombe House, Chieveley, Newbury, BERKS. February Sixteenth 1922. Dear Mr. Chichester, Many thanks for your letter of the 15th inst. I cannot quite understand your people at Conduit Street raising the question of size. I have seen a good number of R.R. cars fitted with straight-sided Cord covers, and every one, so far, with the 33 x 5 size. This particular size, of course, is an oversize, it being fitted on a rim known as the 32 x 4½ rim. There is no such size as the 34. 3/4 tire. Do they mean the 34 x 5 size? This is quite a new size. The rim diameter is 24 inches, whereas the rim diameter of the 33 x 5 size is 23 inches. The Miller Rubber Company make the 34 x 5 size. It is, however, a size mainly used on trucks. Certainly, however, it would be a very suitable size for the Rolls-Royce, and if used on it, 34 x 5 Miller Straight-sided Cord covers would give even better results than the 33 x 5 size. Although the initial cost of this size would be higher, the extra mileage obtained would make the rate per mile work out at the same figure, if not lower. In fact, we would guarantee this. The 34 x 5 Miller size has what we call a flat tread, similar to the attached illustration. The difference will readily be seen on comparing the illustrations shown on the enclosed two folders entitled respectively "$1,136,419.00 spent since 1914 to better them" and "Twenty Four Years Attainment". There is really not much to choose between the two patterns. The flat top pattern is a better nonskid, and a slightly more durable cover. The other pattern is a slightly faster cover, and makes the steering lighter. P.T.O. | ||