I bought my 750 gixxer about a year ago and have been riding it since. It has a ported head, full vance&hines supersport exhaust, k&n individuals and 1 up on the main jets. I love the power of the bike, but it has one very nagging problem. When you reach about 4,000 to 6,000 rpm it hits a flat spot and runs very rich. Once you get passed the flat spot the bike takes off and runs excellent. Would putting a stage 3 jet kit on the bike solve this problem, or should I go back to the stock header and put the airbox back on the bike?