What did you do with whatever else you've got?

[DekF]

It isn't that much louder than the huge standard can. Aprilia fitted an exhaust valve purely for noise regs. it remains closed until 6000 rpm to pass the noise tests. (God only knows how they got away with that one!). I disconnected mine because it caused hunting on a steady throttle.. It's the best sounding bike i've ever owned... 8)

I can only guess how loud it is with the valve open 

Mine with Akra & bellypan to hide the hideous cat