03 YZF450 hesitating under power while wide open. It just started doing this. Seems to run fine in 1-3 gears in most track stuff, but in 4th gear, nearing wide open on last couple of GP races it has a scary hesitation. Feels like it's jumping teeth on the spocket (which it's not) just to give you some sense of how it feels. Quick History: Oil changes every 3rd ride/race. Air filter every ride/race. Never touched the carb, never checked the valves. Bike starts 1st kick after sitting every week. Just changed the plug today & thats not it. The bike is ridden/raced at least 3-4 times per month. I bought it new in June of 2003. Please give your thoughts. Hey greyracer513, looking for your thoughts on this one.