Chinagirl engine, got sick of fiddling with cns carb which wouldn't run, swapped out for NT carb, engine will idle, but only at full choke. The moment I turn off the choke, or twist the throttle at all, the engine dies. It also seems to be idling erratically, it will rev up really high for a few seconds seemingly at random. Also it is easiest to start on the leanest carb setting. I'm stumped as to what could be causing this, and am starting to regret agreeing to look at this guy's bike, anyone got any ideas?