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).
Testing shock absorbers, comparing standard units with Houdaille dampers, and further trials with balloon tyres.
| Identifier | ExFiles\Box 25\2\ Scan094 | |
| Date | 1st August 1925 | |
| R.R. 493a (50m) (D.B. 175 25-9-24) J.H.D. EXPERIMENTAL REPORT. -2- Expl. No. REF: Hs{Lord Ernest Hives - Chair}/Rml/LG27. 8. 25. shock absorbers is difficult to ascertain without an extended test under all road conditions. From our brief experience we should say that the suspension is not affected to a prohibitive degree. We carefully compared the standard RR. shock absorbers with the Houdaille. We could not obtain such good results with the constant friction given by the former as with the hydraulic damping of the latter. In addition, the riding of the car seems to be affected more for a given wobble improvement by the plain friction. In view of these results we are arranging to rig up two hydraulic shock absorbers so that they will offer no resistance to the parallel movement of the axle, but a large resistance to any criss cross motion. We believe this to be the most hopeful proposition at the moment. We have made further trials with balloon tyres. We find that if we depart from the ideal conditions of a perfectly balanced wheel, or do anything to make the wobble worse, such as increasing the transverse moment of inertia of the axle, we have just as much difficulty in damping out these wobbles as a high pressure tyre wobble. Under certain conditions of undulating road surface we have great difficulty in damping out low pressure tyre wobbles. Our great difficulty in these tests is to obtain consistent results. We sometimes obtain flatly contradictory evidence for which we cannot account. We have proved by means of the Chronograph contd:- | ||