We have a 2012 450f monster. 61 hours on it. Once it has ran for about an hour, it will not accelerate when you nail the throttle. Bogs down with some back fire. Starts fine, idles well. It will accelerate slowly to about half throttle. When you nail it, it pukes. What I've done so far: new wire harness, new TPS sensor. Help!!! We love this bike (GNCC RACER). Need it to run the whole race.