i have a 110cc mini hummer quad i tuned it to factory and it runs rich then i make it more lean then its still runs rich the screw it almost all the way in and its still rich and it miss firers so i changed recoil still miss firers i need help

 

I'd take the carb off, disassemble it and clean it. Another option is just buy a new carb for $30.

Joel

 

Strange that it runs rich...Is this a new or used quad?