italjet f50 a/c plug is black and wet

My plug is black and full of oil.

Just fitted a new 21mm TNT carb and 70cc topend but the thing is i dont know how to adjust the oil pump (if it can be adjusted).
I presume that a black/wet plug means too much oil.
Any help would be great.

 

It basically means it's running rich. did you jet it correctly for the new carb and top end or just slap it on and hope it would be perfect?

 

thanks for reply, i thought it was running rich, i tried the carb as it came but have loads of jets. but not sure if i go bigger or smaller on jets if running rich.