Just got an '02 400exc and had a question. I noticed a small flat spot in the powerband around 1/4 to 1/2 throttle. Don't get me wrong, it will break your neck when you snap the gas and then really kick back in at half throttle. I was thinking about a Big Gun exhaust since I had such great luck with one on my KLX. Would this help any? I really don't want a bunch of noise with minimul low end gain. And has anyone had any experience with the Big Gun Quiet Series? Thanks