Don't worry idea is scrapped for me NOT wanting to learn how to ride a 2 wheeled Python this is just a dead end.I do worry with such a system that should it slip you'll then have to fight it to get the trike upright and hope it slips back. If you add several clamps on the round part it would help prevent slippage. Even hose clips may work well enough to prove concept.
Yes I agree , a progressive bump stop would be good , do they make them ? thinking a sort of rubber cone ?I suggest you try to devise soft stops rather than hard ones. Hitting a hard stop as you ride could be somewhat destabilising. A soft stop would likely minimise that effect.
I look forward to any lean figures your adventures into magic leaning measuring sticks produces.
I have succeeded in making a working prototype.DannyC and I are taking tentative steps to build a Arduino tilt monitor so we can record data on a ride to see what sort of tilt angles we achieve.