i was driven by the expensive price of just a 4 stroke engine=£2500 upwards ,as most of us flyers dont have the funds for new ppgs we need to look at other methods to do it,even 2 stroke take a kx80 motorcross engine 28hp throw away the bits u dont need and u have a very powerfull motor,thats cheap to fix and get the bits for without waiting for them alex dell built one and it was very impressive till he had it nicked in mexico,he is making another one,take ppg trikes terry luke has done wonders with the honda vtwins 24-30hp no need for tunning either,all it needs is a bit of tinkering like u said simon.look at other peoples projects and ideas come along.someone will always try somthing just to see if it works,so far im very happy with my little project,i reckon with a 130 prop on a standard gx200 with just the governer removed it would fly well even with a 90kg pilot,