so after about a week of riding i realized the tension in my chain had reduced dramatically. the top part of the chain was hanging a bit and rubbing the bottom half of the chain on the tensioner..obviously thats not good, so i took it and got it shortened, took it home and even without putting it on the tensioner was just a little too short, went and bought a half link put the tensioner on and put the master link back on, perfect! was snug and not rubbing. took it for a test drive around the block and after my last stop sign on the way home my back tire locked up and then started spinning again but only because the gear behind the clutch plate ripped my chain apart..and not at any of the spots with the half link or master link..in a completely different spot.. took it home, pulled off the broken link, replaced it and now its back on the bike.. has anyone had that kind of thing happen before, if so does anyone know why it happened? could it have just been a bad link in the chain that i never noticed before?