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 'Traction' and 'Buttress' tyre treads, noting noise and vibration characteristics.
| Identifier | ExFiles\Box 45\2\ Scan046 | |
| Date | 30th November 1927 | |
| To HS{Lord Ernest Hives - Chair}/GWH{George W. Hancock - Head Chateauroux}/30/11/27 X4050 in. Re Tyres We have been comparing Traction, and Buttress, Treads. We find very little difference between the two treads from speeds of 5 MPH to 30 MPH. At higher speeds the note of the Buttress is of a higher tone, but not what we should consider objectionable. There is a tendency with both type of treads when 60% worn to cause low speed vibrations these vary from 20 to 4 MPH. There are generally three distinct periods. With a road in a right condition these periods are most noticeable, on the other hand they cannot be produced. at times under the same conditions. With new tyres these periods can be got. in fact we do not know of any make of a | ||