Abstract: A lock for securing a bicycle to a dock. The lock consumes little power in operation, with transitions between states in which a bicycle is locked to a dock and released from the dock being driven predominately by force applied to the bicycle by a user. Force applied to the bicycle may drive a latch within the lock to move between a latched and unlatched position. A locking member may be driven in one direction by an actuator and retained by an arm that blocks movement of the locking member. The locking member may be driven in the other direction by spring force, when the locking member is released by movement of the arm, which is coupled to the latch and therefore driven by a user applying force to a bicycle. As a result, a small battery may supply power to the actuator and to communication and control circuity.