I'm not sure if you guys have experienced the same obnoxious sound from the Two Bros slip on, but I think I may have stumbled onto a good fix. I installed a Yoshimura Spark Arrestor P/N TEC-SB-B. I know some of you may be thinking that it's gonna smother the air flow, but It doesn't appear to do anything more than richen it up at Idle and slightly above. I imagine because it has created a lil back pressure. I'm not at all opposed to that. It doesn't snap and pop on the decel like it used to. I had installed the Two Bros Noise reducing tip prior to this, but it still had a lean condition that I didn't like. I removed it and installed the spark arrestor with the screen spot welded to it. That can easily be removed with a file or dremel if you choose to. I left the screen on for now just to experiment with all the throttle positions first. The part installed was $25 delivered to the door. Looking at the pipe now, you would never know it had this installed.