do any of you guys know how to make the air fuel mixture richer cause i think its running way too lean ...eg the header pipe glows red in a short time and when idleing the exhaust pops a bit and alot on deceleration its an 04 rmz 250 and i was wonderin on the side of the carb there was a black thing that you can twist with your finger is this to adjust gas mixture thanks
any reply would be helpfull
any reply would be helpfull