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).
Steering shock when driving over obstacles.
| Identifier | ExFiles\Box 38\1\ Scan142 | |
| Date | 1st April 1924 | |
| R.R. 493A (40 H) (SL 42 12-7-23). J.H., D.{John DeLooze - Company Secretary} EXPERIMENTAL REPORT. Expl. No. REF: Hes/L/1.4.24. We have carried out tests on a smooth flat piece of road by running the car over obstacles. We used some cast iron bars 2" X 4". We found that passing over the 2" obstacles, if they were put at right-angles to the direction of the car, no shock could be felt on the steering. This was the same whether one wheel struck the obstacle or both. It was the same whether we had the disc wheels to give true centre-point or with them dished outwards. In order to obtain a shock it was necessary to place the obstacles at an angle of 45° or more to the direction of the car. With the obstacles arranged this way, we could get severe shocks on the steering under any condition. We carried our tests further to see if we could appreciate a vertical or forward bump deflecting the steering. We arranged a 4" obstacle, and ran one wheel over it at various speeds - after a number of tests our conclusions were that the truely vertical pivot was slightly better under this condition. From the observations in France and also tests we have made recently, we consider the shocks which worry us most on the steering, are blows on the side of the tyre caused when the wheel strikes a pot-hole. We have a 40/50 HP. car fitted with front brakes which has a satisfactory steering. This car has the standard 40/50 lean of pivots (.5° off centre-point), friction washers on each pivot and considerably weaker buffer springs in the side steering tube. contd:- | ||