An adjustment device for changing the relative rotation between a cam and a crankshaft is provided. The adjustment device includes a driven device operatively connected to the crankshaft. The driven device has a first plurality of channels directed radially inward toward a central axis. The adjustment device also has a hub axially aligned with the driven device along the central axis and connectable to the cam. The hub has a second plurality of channels directed inward toward a point radially offset from the central axis.