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).
The characteristics, testing, and fitting of new Dunlop tyres on 20 HP and 40/50 HP car models.
| Identifier | ExFiles\Box 39\2\ Scan163 | |
| Date | 2nd June 1923 guessed | |
| contd:- -2-2 as a bicycle tyre. The rim, having no loose flange, is water- tight. The weight of the complete tyres and wheels is pract- ically the same as the present standard. The peripheral weight is less because the rim and wheel is of a smaller diameter. The width of the tyre at the bead is wider - it has the same angle of stability as the present tyres. There is a scheme on the tyre by which a deflated tyre is prevented from coming off - it also prevents the tyres being damaged, if run flat. The braking is exceptionally good with these tyres fitted but the steering is slightly heavier. We were shown results of comparative tests taken on "Brooklands" comparing these tyres with standard cord tyres for speed and consumption - the differences were very small. The Dunlop Co. have offered to supply us with one set of these wheels and tyres for the 20 HP., and another set for the 40/50 HP. free of charge. We have tried a section of the proposed tyres on a 20 HP. car and find there is clearance all round. On the 40/50 HP., the tyres foul the side steering rod and we shall either have to sacrifice the lock or increase the track slightly by modifying the wheel. If these tyres are successful, they will make an enormous difference to body noises and rattles also wear and tear on the chassis, especially spring shackles. The Dunlop people have been carrying out running tests on these tyres for the last twelve months. Hs.{Lord Ernest Hives - Chair} | ||