Decided my bike could be a bit louder than stock if it increased performance... so I took the muffler off, took out the screws.. shook loose the cat inside.. pulled the end cap off ( hammer and vice grips on the end tip.. just hammer on the grips )... cut off the muffler looking thing on the tip and let the cat fall out... put it back togther and altho running cold really effects it now.. once it's warm.. I'v got 2 MPH more and a lot more low end, and it's not much louder