Abstract: A flexible coupling is formed by a pair of hubs adapted for mounting on a pair of shafts and interconnected by a flexible serpentine grid. One of the hubs is formed as an indexing assembly including an outer hub member having a first series of internal gear teeth, an inner hub member journaled in the outer hub member and having a second series of external gear teeth of a different count, and an indexing ring having external and internal gear teeth that mate with the respective first and second series of teeth. The indexing ring is removable axially from between the inner and outer hub members so that the inner hub member and the shaft upon which it is mounted can be rotated relative to the outer hub member. The indexing ring is then reinserted. When fully assembled, an end ring seals the mating teeth and defines a lubricant reservoir for the mating teeth.