I'm looking at buying this 05 cruiser with a little over 20K miles. As I ride it, I hear an occasional rattle or clatter, not real loud nor in any particular gear when riding it. Kind of sounds like a chain rattle to me. Any thoughts on this? I'm not a mech so looking for suggestions or insight as to whether it's normal or not or possible causes if not. The guy bought it with 16k, so has only put 4.5k on it. He said he's not noticed it. (My nieces husband). Thanks for comments.