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).
Tests on hub wobble, comparing different tyres and suspension configurations.
| Identifier | ExFiles\Box 68\1\ scan0112 | |
| Date | 6th October 1925 | |
| R.R. 493A (50 H) (D.D. 31. 12-6-25) J.H.D. EXPERIMENTAL REPORT. -2- Expl. No. REF: Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}/LG6.10.25. We send you figures taken by a pencil in the end of the hub which demonstrate the relative amplitude of the wobbles with the two types of tyre. These are apt to be misleading unless it is remembered that the tendency to wobble is not always proportioned to the violence of the wobble. Occasionally, a wobble of large amplitude will be difficult to produce and have a brief period. This is possibly a eccentric condition which only occurs because our tests are carried out on perfectly smooth drums. The other results attached shew that friction in the damped pendulum lever does not benefit wobbles to any great extent, that the Hispano type of S.S. springs set up with friction on the ball ends is a slight improvement, and that a solid straight sided tube is better still. We obtained good results on the drums by having the side steering tube rigid in tension and fitting springs only on the inside of the ball ends. So far, however, we have been unable to derive any benefit from this arrangement on the road - we are continuing these tests. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||