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).
Page detailing steering adjustments and the causes and nature of low-speed wobbles.
| Identifier | ExFiles\Box 178\1\ img120 | |
| Date | 13th July 1926 guessed | |
| - 21 - 8. Check wheel gather. Set wheels parallel. 9. Reduce castoring to the minimum to give self-centering. 10. Reduce the strength of the side steering tube springs to the minimum consistent with selective steering. 11. As a last resort, reduce tyre section. V.{VIENNA} LOW SPEED WOBBLES. (a) The nature of low speed wobbles. Low speed wobbles differ from high speed wobbles in that there is no perceptible criss-cross vibration of the front axle while they are taking place. The road wheels merely flap through a large angle rotating the steering wheel in doing so. These wobbles occur at speeds from 10 - 25 m.p.h. as a general rule. They are not dangerous, only highly uncomfortable. One point that they have in common with high speed wobbles is that they cannot be sustained if the co-efficient of friction between the road and the tyre is reduced to zero. For this reason a good non-skid tyre is bad for low speed wobbles. Low speed wobbles are relatively easily cured. Owing to this fact, exact investigations as to what takes place during a low speed wobble have not been made. (b) Aggravating factors. By far the most important item with regard to low speed wobbles is the longitudinal inclination or castoring angle of the pivots. A castoring angle in excess of 2° is always liable to promote low speed wobbles. Other items are:- 1. Excessive freedom or any slack in the steering gear. contd. | ||