HIgh Idle or None 02 YZ250F ??? Stumped

Having a heck of a time dealing with high idle or none. Have went from 180 main / 42 pilot, to 45 pilot, 182 main and every combination back to stock jetting and fuel screw from 1 to 4 turns out and a lot of carb cleaner. Haven't found an air leak yet either. It either roars or dies. Any and all suggestions would be appreciated.

Wow, when I first saw your post I figured it would be a lean pilot circuit, but seeing you have already tried that it is obviously something else. Could the throttle slide possible be sticking, or the cable getting hung up somewhere? That is all I can think of.

Check you air jets, they can easily get clogged with air filter oil. They are located "inside" the intake bell on the back of the carb on the 02 models (not sure on 03) so you have to remove the intake bell to access them. Remove them and clean them thouroughly with carb cleaner.

Thanks to both. May be sometihing with the slide as we had to clean it a few weeks ago with some small deposits that were on it. Maybe from some junk gas and sitting around this winter. The slide "plate" just sits in there does it not? Sprayed the air jets out but didn't take them out. Will definitely do that today.

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