i recently put a jardine rt-1 slip on pipe on my 04 zx6r, i got it with the race baffles in it and i start it up and doesnt really seem that much louder at all i can notice its a little deeper at lower rpms but i can tell a difference that much. is there anyway to make it louder or does it have to break in thanks for the help

 

Pipes do not break in, what you hear is what you get, unless it has removable baffles. If it does, take them out and you will have louuuud!
Welcome to KF.

 

Eventually the fiberglass packing in your muffler will break down over time making the exhaust note louder, but no, mufflers cannot be broken-in. If the internal baffles can be removed, give that a try.