Re: sprocket problems
Alignment/tension...the two most important things to consider with your chain. Shoot for about 1/2 to 3/4" slack in the chain and check the alignment of the chain/sprockets/tensioner wheel. All three must line up near perfect. Most clamp-on tensioner brackets require a slight twist to get them to align with the chain path. Also the bracket should be secured to the frame by some means to keep it from loosening and rotating into the rear spokes. I drill all the way through the bracket and frame and use a 10/32 bolt and nut. Some simply install a self tapping screw through the bracket into the frame, (chainstay). Whichever way you choose it is good insurance against a dangerous and expensive event if the tensioner gets into the spokes.
Age and Treachery Will Always Triumph
Over Youth and Skill & "Charlie Don't Ride"