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).
Tyre noise, its relationship with wear, and comparison tests on different wheels.
| Identifier | ExFiles\Box 30\5\ Scan149 | |
| Date | 7th October 1935 guessed | |
| -2- We have also found that tyres have distinctly different periods of noise as wear takes place. After a few thousand miles, for instance, India and Dunlop tyres are more noisy than when they are new, and from that point they gradually get better until when nearly worn smooth they become quite good for noise, and so for comparative purposes we intend to use new tyres for future tests. The majority of the tyre noise emanates from the tread on the outside edge of the tyre, and therefore as the centre of the tyre wears down and more of the outside edge comes in contact with the road, more noise is produced. With reference to Cadillac and Dunlop Magna Wheels, these were tested against our standard wheels, using the same set of tyres for all tests, and no improvement whatever was apparent. With any kind of wheels, we find that when using a new set of tyres 90% of the noise is produced by the rear wheels. | ||