often the carb doesnt push all the way onto the manifold. air leak there. sometimes its better to just file the carb clamp back a few mm.
have you got the slide in correctly? the slot in its side lining up with the pin in the carb? my friend once removed that pin...not smart.
raise the needle a few notches...
possibility of crank seals leaking. usually under the magneto, as its the thin one. replace with a proper double lip seal, they just squeeze in. the spray of oil behind the magneto is a good indicator its leaking.