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 a tyre company regarding chafing issues between the tyre cover bead and the inner tube on well base rims.
| Identifier | ExFiles\Box 29\4\ Scan081 | |
| Date | 13th March 1931 | |
| COPY OF LETTER DATED 13th March 1931. FROM :- India Super Tyres West Midland Ltd. 21-22, Cambridge St, B'HAM. TO:- T. BARCLAY ESQ, Metchley Grange, Harborne, B'HAM. Dear Sir, Confirming the writer's conversation with you recently, regarding the chafing that takes place between the toe of the cover bead, and the inner tube on your 33 x 6.75 baloon tyres, fitted to wire wheel, well base rim. It is our opinion that 5.50 section, is the largest section that should be fitted to this type of rim. Whilst this rim does excellent service with the small section tyres, it is not successful with the 6" and over balloons. The roll of the tyre, and the tendency of the rim to spread, causes the bead of the cover to chafe the inner tube, and even the extra long toe of soft rubber on the cover today, has not made much improvement. The straight sided American type of rim, should be used for the larger size. This type of rim permits the endless rubber spreader, to be used in conjunction with the cover on the base of the rim, and thus saving the tube from any nip made by the movement of the cover. In support of this argument, we might mention that the wheels and original equipment on your Rolls were made by the same firm. We have retained the tubes taken from them, which after 4,000 miles, which we understand was the mileage you told us these tyres had done, the inner tubes in places were nearly chafed through by the cover bead, in the same manner that our tubes have been chafed by the INDIA SUPER COVERS. Most of the spokes are anchored in the outer flange of the rim, which in itself has a tendency to spread and pull this side of the rim lower than the opposite side. Whilst we have been able to protect your tubes by fitting a strengthening band on the base, and fitting special rubber bands on the toe of the covers, in our opinion it is only a temporary measure, and should not be necessary on a high class car. This, however, is what we have found from experience, and we should prefer to deal with a flat base rim for the larger sizes. However, should your tyres give the slightest sign of further trouble, we shall only be too pleased to deal | ||