Wow! 75mm is an impressively low height for the bar. I am geuessing that is its lowest point? I don't think even those with 73mm banebots wheels, like myself, will be safe! It will be at the very least a tyre nibbler and at best seriously dangerous.

Also, given the bar is much lighter I would say 4K is a good max speed. Anything less than 3 and I don't think it would have the inertia to damage any highly armoured targets.