I'l tell ya what, I got my thunder alley pipe, and did the bk mod. rode it last week, spent most of the day re-learning the bike. When I demo'd the pipe, it softened the bottom just a hair, and the mid and top end just ripped. Well, the bottom was unbelieveable, and the top end horsepower was plain scary. I was going to gear it down, now Im thinking up. Its actually more than I wanted to be perfectly honest. After spending the day on the thing and a couple of adjustments to throttle play @(silly stuff)I really like it alot. I over jumped everything right at first so the thing works for sure.