In at least one illustrative embodiment, a clutch may comprise an outer race, an inner race, and an engagement assembly disposed in a space located radially between the outer and inner races. The engagement assembly may comprise a plurality of locking members and a biasing shoe frictionally engaged with one of the outer race and the inner race. The locking members may be configured to move with the biasing shoe within the space between an unlocked position, in which the locking members are free to move relative to the outer race and to the inner race, and a locked position, in which the locking members are wedged between the outer and inner races to couple the outer and inner races for rotation together.