Hey guys, i've got somewhat of a low spot on my chain... that doesn't make sense, let me explain. Heard a little clunking... was only around 10/20kp/h then was gone. today spun the chain around a bit and noticed at a certain point, the top part of the chain dips heavily and is really loose. The clunking coming from it tapping a plastic area just below the top of it. i've tensioned my chain but didn't make much difference. could it be my sprocket has worn? the rear spock is fine, and doesn't have any abnormmalities though, so i'm thinking it's the one behind that cover. unfortunately, i have no ratchets, so can't really open the cover at the moment What do you guys think?