The first step is to confirm that the tensioner is functioning. Check the set screw by loosening the nut, turn the set screw in, count the turns, loosen it up the same amount, tighten the nut again. it should be 1-2 turns out.
start the motor, look at the big nut as you rev the motor, it should move
there is a spec for cam chain length, go here and get a factory manual
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