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).
Tests conducted to understand the cause and effect of steering wobbles in vehicles.
| Identifier | ExFiles\Box 21\4\ Scan128 | |
| Date | 2nd January 1923 guessed | |
| contd:- -2- we are using now. We proved that tyre pressures made no difference to the period. We proved that whether we had buffer springs in the side steering tube or whether we had a straight tube and no springs, the period was the same. We proved that making the front springs choc-a-bloc by fixing wood blocks between the springs and the frame and cramping them down by means of screwed bolts, we did not alter the period. We found that varying the weight or by removing the engine did not alter the period of the wobbles. In fact, all the various tests we have carried out on the steering, we have not been able to measure any difference in the period of the wobbles. In some cases the alteration reduces the wobbles to such an extent that our apparatus would not record them, but in those instances we could not observe any difference in the period. Although the various alterations did not alter the period of the wobble, we could make considerable difference in the amplitude of the wobble or the car speed at which it came on. We found that we could always cure any wobbles by making sure that the pivots leaned slightly forward and not backwards. With the steering under this condition, of course, the wheel would run away as soon as the steering was turned the least degree. We found also that wobbles are very very difficult to obtain on greasy roads. A car that might be impossible to drive on dry roads, is practically free from wobbles on greasy roads. contd:- | ||