I have a "99 KLT with a nice rattle in the muffler. I know that it's caused by a loose baffle inside the muffler. My question is can this do damage to the engine in anyway? Im going to replace the exhaust system at some point but should I be concerned. Also the bike has 39000 miles on her. Is this the norm for the wear on these bikes to need to replace the muffler with said miles.