A pivoting chain guide and tensioner assembly for use with an endless chain loop comprising: at least one bracket plate, a tensioner attached to the at least one bracket plate, and a guide attached to the bracket plates. The bracket plate surrounds the chain at least partially between a driving and a driven sprocket and at least one of the plates has a hole for a pivot at a center axis. The tensioner comprises a tensioner arm with a chain sliding face for contacting the outside of the chain and a biasing means. The guide has a chain sliding face that contacts the outside of the chain. When a high local load is applied to the chain, the load is received by the end of the guide, forcing the guide to move away from the chain, such that the bracket plate pivots, moving the tensioner relative to the chain.