RE: Opinions please!!! New engine running crappy
Contrary to what some here might think, the issues with your engine aren't solved by getting a new one. And with a good pipe you may find that it has ample power (for what you want to do).
IMADMAN has posted the factory settings for your carb, give that a try. It'll be running a bit rich with those but that should be good for now. Try increasing the idle speed to keep the engine ticking over by turning the idle screw clockwise until you get a nice steady tone from the engine but without the clutch biting (turn it up too high and the wheels will start spinning).
What 2 stroke oil are you using?