Originally Posted by terbo

I just had a quick thought about break-in on the mufflers: FI uses straight through glass pack mufflers. These are literally packed with a fiberglass material to halo muffle the sound. From the looks of it, the Berk uses a type which has chambers that cause the audio waves of the exhaust to bounce off the chambers and into each other, canceling themselves out to an extent. It is possible that without a few cycles that the FI style glass packs would not seat properly and you could eventually blow the glass right out of the muffler, although I have not heard of this happening. The Berk exhaust should not require "breaking in". I also could be very wrong about everything I said. What do I know? I'm just a mechanical engineer :P