I NEED HELP!

[Pat Conlon]

my 1349 motor has 10:25 compression pumping 200 PSI....... runs great on pump gas.  

That sounds about right. Thinking in simple terms of relating compression pressure vs. surface area of piston:

If stock compression is 180psi (new motor) and stock piston size is 77mm dia. (a= 4654) then Frank's  82mm piston (a=5278) with ~12% more surface area should be able to run ~12% more compression pressure: ~201psi, and have the same ratio as stock.

However, if Carterc's bike has compression of 200+ psi and 77mm pistons.....I would be careful with pump gas.