I have a brand new baja 300 extreme atv. It would only stay running at half choke. I tried to adjust the idle screw and air/ fuel mixture screw and it didnt really help. If I put the choke in all the way it just stalls right out. If I leave it out a little it will stay running and I have to give it a lil gas when riding to keep it from stalling out.

 

Sounds like its lean. Check the carb jets etc. maybe some crap got in there. Remove carb, clean and try again.

 

What he said. [img]i/expressions/face-icon-small-smile.gif[/img]

 

What I found on mine is that the gas tank had a whole bunch of silicone looking stuff in it. Completely clogged my carb, and fuel lines. So i went to autozone got some more fuel line and fuel filter, and cleaned out the gas tank and no problems since.