Urk. Yes, you're quite right, I lost a minus sign somewhere.


Yes, OK, yes we do. Both springs are acting so that the further up the kingpin the slider is, the greater the downwards force on it. (In the case of the rebound spring, the lesser the upwards force, but that's the same thing.)

So you really do have a suspension that gets less stiff once excursion reaches a certain amount. Presumably that excursion isn't very large? i.e. the rebound spring isn't much longer unstressed than it is installed with the car at rest?

Peter