Chain Tensioner and Chain Damper
One second fitment
The principle of ROLL-RING chain tensioners is based on two simple effects:
The elastic ring engages with the chain strands and rolls between them in a pre-stressed condition taking up the shape of an ellipse.
The constantly opposing movements of the load and un-load strands cancel each other out, to the "zero sum movement", thereby holding the ROLL-RING in position.