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).
Test report on vehicle suspension components, including braking, springs, and dampers.
| Identifier | ExFiles\Box 5a\3\ 03-page179 | |
| Date | 14th December 1931 guessed | |
| -13- six brakings from 60 to 10 M.P.H. has been carried out during each run apart from braking due to traffic. Both the oil drain pressings were knocked off early in the test. The rear brakes developed bad groans. FRONT ROAD SPRINGS. Low Rated type - Rolled Eye (eachend). O.S. N.S. Drawing No. F.57900 F.57900 Loaded lbs. 704 707 Initial Camber. 4.5" 4.5" Material. S/SLM. S/SLM. The front road springs were too light for the load of the body which caused severe bumping at the front. We have not had any failure of the springs and when examined externally, lubrication appeared to be ample. The bijur feed on the N.S. spring to the front axle broke at the outlet of the coil situated in the housing of the rear shackle. The pipe was so arranged that it prevented the free movement of the coil. We were of the opinion the coil would operate better if it was coiled in the opposite direction. We took half a coil off and have not had any failure during the remaining part of the mileage. REAR ROAD SPRINGS. Rolled Eye type ( each end) fitted with plain grooved bushes. O.S. N.S. Drawing No. F.57204 F.57204 Loaded lbs. 1008 1018 Initial Camber. 5.940" 5.900" Material. S/SLM. S/SLM. The riding in the rear of the car was very good up to a speed of 50 M.P.H., above this speed the rear passenger was thrown off the seat. We increased the load of the dampers and improved this condition but made the lower speeds hard. The springs do not show any failures. There was oil on all the sides of the leaves when externally examined. The bijur pipe feeding the O.S. rear shackle dried up. We could not find any stoppage in the pipe line but the spring shackle oilways were stopped up with swarf. It appeared to be this that had prevented the lubrication. The bijur drip plug was O.K. The N.S. bijur supply failed through the bijur pipe becoming chafed by the gusset plate distance piece but the leak of oil was noticed immediately and no loss of lubrication took place to the shackle or spring. FRONT & REAR SHOCK DAMPERS. (split piston type). Front. Loads set. L.F. 90 lbs. R.F. 115 lbs. | ||