Hi This may sound like I am hearing things, but I don't think I am. I have a 2001XXY Blackbird. I roll the bike out of the garage each day, recently I have started to hear noise from either the rear wheel, sprocket or chain, I don't know which. It is a click that is linear to how slow or fast I push or ride the bike. It is only a very subtle noise and barely audible over the engine It may have been there before and I have just not noticed it.....but..... Any ideas?