Okay so I just got a 05 YZ250f. Cleaned the carb twice and still having issues with the choke. Bike has maybe 15 hrs of riding on it and had old fuel in it for multiple years. So as I stated I pulled the carb apart twice. When I first got it I open the fuel and it poured everywhere, so reason being for clean number one. Still had issues with it only tunning with choke on so I pulled it apart again. Lone behold the pilot was clogged up. So I cleaned her up again and same deal. Only runs with choke on but better on the start and the blip of the throttle