This what I've had for the last year, and had no problems other than running a little rich: Model (YZ or WR 250F):2006 WR Timing (WR-YZ):WR Main jet:180 Pilot Jet:Stock Fuel screw (turns out):3/4 Needle model/Clip position:JD blue, 4th Airbox lid (on or off):Snorkel off, holes cut Pipe:Stock, GTYR insert Altitude where you ride:0-1500 ft. Temperature where you ride: 60-95 Other mods:AIS removal, gray wire, ZipTy fuel screw,YZ throttle stop, ACV diabled This weekend I removed the rear baffle on the stock pipe, and set the cam timing to the YZ setting. Before I would twist the throttle one time and hit the button and she'd fire right up, now the bike won't start unless you hold the throttle open 1/4 of the way, idles funky and has a little bit of a bog again, although on test rides definitely has more power. I tried adjusting the mixture screw and switching around jets, and it seems like it's still running rich because going down to a 175 main seemed to make it better. Any ideas?