The Muzzy is particularly quiet. That's all I can add to this unfortunately. My 14 is always the quietest bike at the track whenever we go that has an aftermarket exhaust on it and it's almost as quiet as the bikes with stock exhaust. I have two canisters and removed the guts from one of them. With the gutted canister the bike will wake the dead so it's the canister design and packing inside that makes the bike so quiet. Still makes power even though it's super quiet though.
2009 Monster Edition ZX14, 70" wheelbase, 16-46 gearing, air shifter, Shinko Drag Radial. 2005 Turbo Hayabusa, 74" wheelbase, 16-43 gearing, foot shifted, Shinko Drag Radial. 2001 GSXR 1000, long, low and not stock.