Question for the carb guru's.. My 2010 WR300 at about 1/4 throttle, steady state, cruise, doesn't matter what gear, the engine is just not running clean, sputters, almost like it's cutting out. The engine starts first kick. Idles perfect, tons of power, it is smooth power when rolling on the throttle, wide open throttle is great. Just when your not in the power band and holding the throttle steady it sputters.. I think I may be a little lean, there is no spooge, race head, stock mikuni carb, 40:1, 3000 ft. 17 deg. cel. 94 octane, 420 main, 40 pilot,gay needle, clip at the 2nd setting down from the top. I haven't had a chance to pull the plug.. Just looking for some direction on this one... thanks in advance, Steve