I agree with jhald, I have the TRC and I removed the silencer and I have the same slight rattle. I think it is a design flaw, but neither the less I only hear it at idle and low rpms. Other than that she be screaming. I really don't even notice it now, I've had my system on for 2yrs and it's a part of the normal sound of the bike. So chin up and ride it, GONE