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).
40/50 steering, comparing centre-point steering with modified pivot lean.
| Identifier | Morton\M20.2\ img016 | |
| Date | 11th April 1924 | |
| more wisdom on centre point steering R.R. 493A (40 H) (SL 42 12-7-23). J.H., D.{John DeLooze - Company Secretary} EXPERIMENTAL REPORT. To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to CJ. RS.{Sir Henry Royce's Secretary} c. to DA.{Bernard Day - Chassis Design} H.{Arthur M. Hanbury - Head Complaints} c. to EY. WDR. Expl. No. REF: Hed/AC111/11.4.24. Y9430 Y9450 SECRET 40/50 STEERING - EAC.111. After a number of comparative tests on various cars over different road conditions, we are now satisfied that altering the transverse lean of the pivots so that the contact of the tyre on the road is .5" off centre-point, does definitely improve the steering by reducing the road shocks on the steering. When we revert to this standard 40/50 pivot lean, the arrangement of the steering with 4-wheel brakes will then be identical to the standard 40/50 except that the bearings on the pivot are much closer together and will therefore have more friction and heavier loads. With the centre-point steering we get a constant fidgeting of the steering wheel even on fairly smooth roads which becomes excessive on bad roads. From our tests it would appear also that centre-point steering is worse for low speed wobbles. We shall have to arrive at the right compromise between the buffer springs in the side steering tube, and the friction on the pivots. If we fit weaker buffer springs with centre-point steering we get bad low speed steering wobbles. If the friction in the pivot is excessive and we are using weaker springs in the side steering tube, we get a steering which is inclined to wander and has a lot of contd:- | ||