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).
The causes of wheel wobble, tramping, and oscillation in a front axle unit.
| Identifier | ExFiles\Box 29\1\ Scan277 | |
| Date | 15th September 1925 | |
| - 5 - is off the ground inclines the wheel which is on the ground forward, that is, makes it look in towards the frame, but immediately the energy of the wheel which is in the air is absorbed by reaching the extreme of its backward travel, the drag of the road, which now becomes the main factor in the whole issue, forces the wheel which is on the road in turn back towards the central position, and the periodic swing of the axle at this point again lifts it, and so forces the motion to continue and become more aggravated with every completed oscillation. The marks on the road resulting from this action would be a series of curves struck from some point further offset from the chassis centre, but on the same side as the wheel which happens to be on the road, that is, a series of curves convex to the axis of the chassis. It is interesting to note that in the early diagonal or angular motion of the axle as affecting the stub axle, the resultant motion between the spring and the side steering tube gives an impulse in the same direction as the tilt on the wheel itself gives, that is, it gives a backward pull to the offside pivot and wheel, and thereby assists the early small periodic effects which finally result in fearsome high speed wobble and tramping of the front axle unit. wheel By | ||