Fun physics sim

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Been doing some physics stuff in Cinema 4D which now uses the Bullet physics engine and is a joy to play with. Here's a motorbike I'm working on. This is just testing the suspension as I've been having trouble with it bottoming out too much, and applying enough power to the ground. The cool thing is you can ride it round real time using a gamepad. Then bake it to create the final animation. Monos, powerslides and stuff can all be done but I need to make the riders weight distribution adjustable too. So do you think it's starting to look reasonably realistic? (I mean the physics, not the modelling. My modeliling skills are 5yo level)
[youtube]http://www.youtube.com/watch?v=z3qsYsqNJgg[/youtube]

the phyics are looking quite good,
i would soften the suspension a little but other than that i think you are pretty darn close.

But softening the suspension any more makes the front wheel slam into the forks/mudguard which ends up with the rider doing an up-ender. I took most of the bikes measurements from a yz450f (2010 model). The model is just a quick mass distribution around the features of it, with the COG centered where I was told on dirt bike forums it should be. Obviously you can't just take real world masses and get something to work in a sim. It's a lot of f*****g around. The rear suspension works like on a real bike. The spring attaches to the swingarm at around the same position as on a real yz. And I read up on how much preload/sag should be there. But the spring dampening in c4d just doesn't seem real-world friendly and is doing my head in as well.

you are right, its the speed and not the distance that is off,
hmm what linearity do you set the springs for?

any place where you can define your own?

You've just given me an idea, I've always had trouble with springs in c4d. You can't change the linearity of them and I think Maxon may have boo-booed a bit with them. I can easily create my own spring forces. I don't know if it will speed up or slow down the real time performance but will give it a go. I have some data on shock forces on the front suspension of a yz450 in competition so will try and apply it. I'm pretty sure it's non-linear. Not so much the spring forces but the dampening. Can't believe I didn't think of that earlier. It will allow much better tuning. I did a similar thing with a heli sim, where I programmed the lift using throttle and pitch curves taken from my real rc heli.