I think it makes them louder. I was just talking to the mechanic last week that put on my Classic IIs. He said these exhausts have a pipe going down the center and has holes through to the outside chamber which is packed. He's right, I just stuck a tape measure down this pipe to at least 24" so there aren't any baffles like the stock pipes. Removing the packing would reduce the sound absorption resulting in a louder sound coming out of the pipe.
Here's an S50 with Classic IIs with the packing removed. I can't compare how loud they are compared to mine but the overall sound seems to be pretty accurate.
[youtube]TRz7trbluHI[/youtube]
This is my favorite Classic II video and this is how I wish I could make my bike sound. Note that it doesn't have the popping sound that the first video shows. This guy says that he shortened the baffles but I haven't figured out what he means.
[youtube]nPDUg-Y4uZs[/youtube]
