I had a puch magnum e50 with 16x40 gearing, 70cc airsal. A techno boss got me to 48mph, did a direct swap to a techno circuit. It had better midrange, but topped out at 42-43mph. I doubt the circuit pipe could rev out to 10,000rpm. I'd try swapping to an estroil and bump the timing back a few degrees to 16-18 btdc. Squish can be tighter but you'll gain more compression too.