I have the MVVS 58 Prosport and I understand that the factory reps say not to exceed 6,000 rpm static. Prop your motor so that it doesnt exceed 6,000 rpm on the ground. Your elevation will determine your prop size. I have a Bolly 24x10 wood turning 5,900-6,000 rpm at about 5,000 feet in elevation with a Slimline Pitts DA-50 modified to fit. I am at 40:1 and the motor is still running rich on the low end. I only have a little over a gallon through it. The motor will only get stronger with time. If I want to use the tuned-can I will have to go to a 26x10 prop to keep it in the 6,000 rpm range.

Dont get caught up in all the hipe about an engine, if it doesnt work out for you then return it or sell it. They just recently started making planes for these motors check out the new 75cc size planes, these are going to be perfect for these engines with the tunned canisters. I am currently flying my Prosport in an 18lb BME YAK and it has plenty of spare power at 6,000 rpm and thats at 5,000 ft elevation. In fact today was the maiden flight and it was fun!

My only complaint about the motor is it is dirty, even at 40:1 I get alot of slick black gunk on my plane.[&o] I cant wait till it cleans up, I have a ways to go to lean it out.