I'm looking for some trouble shooting help. On my 04 wr 250f the throttle slide plate adjusting screw needs to be turned way up in order for the bike to idle. It is not idling fast, but the adjusting screw is turned up so far that the slide plate is up off the bottome of the intake port by about 3/16". I don't think that is normal? I have taken the carburetor apart several times and cleaned it with no change. Is it my jetting? If so what should I be changing? Someone said it could be an air leak. I don't think that I have an air leak. How do I know for sure? Any advice would be great. Thanks.