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).
Comparative steering tests for the 40/50 model, focusing on pivot lean and centre-point steering.
| Identifier | ExFiles\Box 182\M20\M20.2\ img016 | |
| Date | 4th April 1924 | |
| R.R. 403A (40 H) (SL 42 12-7-23). J.H. D.{John DeLooze - Company Secretary} more Hs{Lord Ernest Hives - Chair} words of wisdom on centre point steering ORIGINAL EXPERIMENTAL REPORT. Expl. No. REF: Hea/AGL/4.4.24. To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to CJ. RG.{Mr Rowledge} c. to DA.{Bernard Day - Chassis Design} E.{Mr Elliott - Chief Engineer} c. to EY. HOR.✓ S E C R E T. X9430 X9450 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: | ||