I have a question that I hope all you NSR guru's can answer. I have a 92 NSR250 SE I have fitted TYGA pipes, moded air-box and performed a wire-splice. I just did a top-end rebuild on the motor. When I'm warming up the bike, I blip the throttle to about 6-7000 RPM and I would hear 2 distinct popping sounds from my exhaust. What does that mean??????