yes this flickering is also present in mine. I suspect, it's because the tire slip ratio flickers, those huge reaction torques go back to the engine. I still have issues with the driveline especially with powerful engine ~400Nm.
with 1000hz I get some nasty angular velocity flicks when the car is powerfull (lets say 700nm at peak engine rpm) Its causing the clutch to disengage and do some funny things
But meanwhile I managed to improve my tire, and it's now much better over rumblestrips and bumps.
Here are some experiences;
Now I handle the wheel as a separate object (only logical means) and apply separate forces to that. Also I use an other spring representing the rubber. So that spring force is pushing the wheel hub upwards and the gravity and the suspension is pushing it downwards. This generates the movement of the wheel hub as well the suspension spring's. The fx and fy forces are applied at the contact patch and the suspension spring force is at the attach position.
The fy should be applied at various places, though to have proper lateral jacking, but for now this is still satisfying.
An other thing that proven to be important was the tire damping. Some articles mention 500N/m/s, but i'd go for 5000. Maybe I'm overcomplicating it but using variable damping produced the best result. That means, the damping changes as the tire deflects.
Still thinking on surface related camber. It would make sense to change the camber depending on the tire orientation with regard to the ground. But the old pacejka (89) is not designed for motorcycles so not good with high camber values.
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