[KrazyCarl92]

Originally Posted by Brandon_L

Im not entirely sure what you mean by the first bit. But it sounds like you'd have them loose when you're putting the chains in and slide them around to get your tension, then tighten them down. Your first sentence made it sound like there is another tensioner somewhere, though.

This other tensioner is most often a cam mounted inside the tubing that can be rotated to adjust the position of the bearing block along the length of the slot, and thereby properly tension the chain when the bearing blocks are loose. Then the bearing blocks are tightened in place to help maintain their position until they need to be adjusted again.