20-10-2019, 07:35 PM
re Robert Leighs reply
As with many old cars to some extent, the steering geometry of a Seven is not "correct". If the steering box is locked rise and fall of the axle causes steer. This can be shown by rocking the car with the box normal. The steering wheel should remain still but turns remarkably. Same if you drive hands off over winds and waves. Hence many claim (including that great authority Nicholson!!) that some steering box play is desirable (and I have heard this view from other exponents of other old cars, although have always striven for very little). Except when things were really serious I developed the habit (never lost!) of steering with one hand as this gave a desirable resilience to the steering feedback, the wheel moving instead of the road wheels.
(I have been involved with Javelin cars for eons. These have screw adjustments which influence bump steer. Cars correctly set up without are markedly less fatguing to drive on winding and wavy surfaces. Note that with straight axle cars in particullr some steering feedback from gyroscopic effects is inevitable.)
Modern cars with perfect geometry have tight joints which dampen shimmy but older cars rely on the self centring to restore minor deflections if some part of the linkage is stiff restoration is blocked and the car wanders constantly.
As with many old cars to some extent, the steering geometry of a Seven is not "correct". If the steering box is locked rise and fall of the axle causes steer. This can be shown by rocking the car with the box normal. The steering wheel should remain still but turns remarkably. Same if you drive hands off over winds and waves. Hence many claim (including that great authority Nicholson!!) that some steering box play is desirable (and I have heard this view from other exponents of other old cars, although have always striven for very little). Except when things were really serious I developed the habit (never lost!) of steering with one hand as this gave a desirable resilience to the steering feedback, the wheel moving instead of the road wheels.
(I have been involved with Javelin cars for eons. These have screw adjustments which influence bump steer. Cars correctly set up without are markedly less fatguing to drive on winding and wavy surfaces. Note that with straight axle cars in particullr some steering feedback from gyroscopic effects is inevitable.)
Modern cars with perfect geometry have tight joints which dampen shimmy but older cars rely on the self centring to restore minor deflections if some part of the linkage is stiff restoration is blocked and the car wanders constantly.