just a perspective: being someone who regularly takes both bikes and cars to the track i can say that riding a bike is a very PHYSICAL experience. that means the body positioning, body weight transfer, the feeling of dragging knee along the pavemet are what it's all about. i would think that this experience would be very diffcult to simulate. none of the arcade bike games even come close. driving a car on the other hand is a 'sitting down' exercise that is pretty well suited to simulation. of course the g forces and 'seat of the pants' feedback are all missing but i've found with a decent ffb steering wheel the experience is quite satisfying. and no, motion simulators don't help - i've tried a bunch, from simple to very fancy, and i've yet to experience one that helps the simulation rather than distracts from it by providing confusing/unrealistic feedback. no feedback is better than bad feedback.
my point? i think that the physics of bikes can be simulated well (although it's a subject complex enough that many of the professional bike race schools don't agree on things as fundamental as how a bike is steered!). but the experience just doesn't lend itself well to simulation, at least not with any controller hardware i've ever seen.
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