A pump that includes a piston moveable along a first axis and an eccentric cam positioned about a second axis, wherein the second axis is substantially perpendicular to the first axis. The pump also includes an actuator positioned adjacent to the cam and configured to move the cam along the second axis. In addition, the pump further includes a cam-adjacent bearing positioned between the piston and the cam, wherein the cam-adjacent bearing remains positioned substantially along the first axis upon movement of the cam along the second axis.