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).
Technical explanation of the semi-servo braking system's characteristics and effects on vehicle handling.
| Identifier | ExFiles\Box 178\1\ img093 | |
| Date | 8th July 1924 | |
| - 2 - Hs{Lord Ernest Hives - Chair}2/LG8.7.24. It is for this reason drivers should be impressed that they should make a habit of releasing the brakes when actually turning a corner. Very efficient front brakes also increase the wind-up on the front axle and springs so that the car, when it pulls up, stops with a jerk due to un-wind of the axle and springs. It is also possible with very powerful front brakes to get a high speed brake jagger on the front brakes and springs. With the RR. semi-servo system, the front brake pressure is supplied wholly with the servo, for instance, it is possible, if the car is going very slowly, for the foot pedal to be operated so quickly that the rear wheels are locked by direct pressure before the servo comes into operation and therefore if that condition occurs, there would be no front braking at all. It is very unlikely for this to occur, and if it did, the car would have to be travelling so slowly that rear braking would be sufficient. Another feature of the semi-servo is that if the brakes are applied and the rear wheels lock, no extra braking can be got on the front by pressure on the foot pedal. On most servo systems, where the direct pedal pressure goes to all four wheels, it would be possible. With the RR. system, when the rear wheels lock, (which means the servo stops rotating) whatever pull is on the front (contd). | ||