Philip, it is had to follow you question. I am assuming that you ask another question about the engine, but this question is not appended to the first, nor is there a link to the other thread.

How is your engine not running as it should? Hove you gone through adjusting the needle valves, IE set the high speed mixture at full throttle for max RPM then back of by 500 rpm, then set throttle as slow as it will go and keep running and then lean the idle for max rpm at that threottle setting, then do both adjustments again.

All this assumes that you have a tach so you can see what is going on. If you don't have one, buy one or at least borrow on from a club member. A tach is an absolutely necessary for tuning a four stroke until you have a lot of experience with the engine.

Don