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).
Investigating high-speed steering wobbles on Phantom and Silver Ghost chassis.
| Identifier | ExFiles\Box 28\4\ Scan298 | |
| Date | 12th August 1925 | |
| R.R. 493a (50 H) (D.D. 31. 12-8-25) J.H.D. EXPERIMENTAL REPORT. -2- Expl. No. REF Hs{Lord Ernest Hives - Chair}/RmL/LG18. 8. 25. contact is set to measure every thing over a certain small amplitude. On the record in question we could feel no high speed steering wobbles on the wheel below 57 m.p.h. whereas, on the record there is still signs of a wobble at 53 m.p.h. This is probably due to the fact that we are using weak side steering tube springs to reduce the tendency of the wobble on the car in question, which probably allowed the wheels to move through a considerable angle before transmitting shocks to the driver. We have carried out further tests to ascertain whether additional weight on the front axle is liable to increase the violence of high speed wobbles. Our tests so far shew that we can detect no difference, even when the weight over the front axle is increased by 3 cwts. We have brought up high speed wobbles on a Silver Ghost front wheel brake car with high pressure tyres. These wobbles took place at speeds in the neighbourhood of 60 m.p.h. We are now comparing the Phantom and Silver Ghost chassis under exactly similar conditions. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||