I am thinking about putting american custom slip ons on my 2011 classic ,I want it louder, But i dont want to remove the cat yet, Will i get a lot more sound or is it not worth it. I would be getting the growl pipes, Thanks Danny.

 

the cat is the bottleneck to flow and sound.

if you look at these open pipes, you'll see that they are only legal on the cat bikes ( 2010+), they'd be way too open on an 09 or earlier

http://www.harley-davidson.com/gma/g...1&default=none


some riders report good results with the stock mufflers once the cat is removed or the header replaced, but slip ons could be in the future


Mike