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).
Technical memorandum discussing steering and suspension issues like wheel wobble and shimmy, and proposing potential solutions.
| Identifier | ExFiles\Box 43\2\ Scan190 | |
| Date | 21th December 1926 | |
| Contd. -2- Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}2/T21.12.26. the cross steering tube, and that you do not try to fit front springs of the maximum flexibility. (2) We have never experienced a case of tramping that was not connected with wheel wobbles. We have also never experienced a species of tramping whose periodicity did not vary with the speed of the car. It is therefore rather difficult for us to appreciate your trouble. We do not say that "wobble" does not occur on rough roads, we only say it is easier to detect the periodicity of a wobble on smooth roads; on rough roads the periodicity is liable to get mixed up with road shocks. We also do not say that wheel wobble does not occur on wet roads - it is less violent when water makes the surface of the road really slippery. Our extreme case of rubber on flooded cast iron can only be reproduced artificially. Very few road surfaces outside towns in England become really dangerous when wet. Therefore we are still of the belief that you are suffering from an incipient shimmy. If you have no lost movement in the front dampers and loads of 40 lbs. up and 80 lbs. down, we consider that you have the best compromise for wobble and suspension. Slightly stronger front springs should give you an improvement with regard to tramping. We consider, however, that the most hopeful method of overcoming the trouble is to put friction in the steering. Try 1200 lbs. load on each ball of the cross steering tube. Also try a change of front tyres, some makes | ||