Ach, Just encountered the issue of colliding with segments of the landscape!
@Cristineltrl seems to have these issues solved - and links to this: https://www.youtube.com/watch?v=qOe3lYCA1YA&feature=youtu.be
Which I hope will contain some answers (<insert old git grumble about people doing videos instead of write ups here>)
/me watches a good bunch of the video
Fantastic!! The key feature I was missing was oddly in the collision type of the axle.
I had set “collision enabled” to “query only” - which sounded sensible, as I desired no collisions, but it seems to require collisions of some sort to simulate the physics.
Changing “collision enabled” to “query and physics” then ticking “ignore” for all collision types has totally fixed my wobble!
I am mystified as to why this may be, but am extremely happy I can now get the the core functionality of making my bike steer and balance correctly. I’m aiming to do both a “fully manual” mode, where the user directly manipulates balance and steering, as well as an automatic mode, where the user controls the camera, with the bike attempting to balance and steer to match.
Thanks again, @BoredEngineer, @Cristineltrl and UnrealTek ( https://www.youtube.com/channel/UCX44PoFn-gUJ2_8VYAaVrbw )
I hope anyone else trying to do complex constraints, steering joints, suspension and wheels with proxy bodys that have mis-configured collisions may happen across this thread and solve their problems too 