Cylinder and carb issues


New Member
Local time
6:27 AM
Feb 4, 2024
I recently bought a new 66cc China motor for my bike, it had lots of trouble starting and frequently died. The carb throttle needle had lots of black gunk on it and the cylinder looks terrible. Bellow are images attached. Can someone please help me fix this or do I need a new top end.


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The gunk could be coming from the gas tank,something to look for,the cylinder looks ok to me but it hard to tell on pictures.
Take the petcock off the tank and rinse the tank out with some clean fuel, dump out the tank into a white plastic container to see what comes out easily. Take your carb apart and clean it out as well. You can follow along on the carb thread here.
I already cleaned out the carb but I haven't cleaned out the tank, I have a fuel filter installed. When I try to start it after cleaning it instantly starts for a few seconds then dies and won't start again. I'll clean out the tank and try.
Sorry for the radio silence but to keep it short, the engine doesn't work (i suspect a case vacuum leak) So I bought a new one