An adjustable surf wake system enhances a wake formed by a watercraft travelling through water. The system may include a flap for deflecting water traveling past the stern of the watercraft, and/or a positioner operably connected to the flap for positioning the flap relative to a longitudinal axis of the watercraft between a neutral position and an outward position. Positioning a port flap in its extended position enhances a starboard surf wake, and positioning the starboard flap in its extended position enhances a port surf wake. A wake modifying system for modifying a wake produced by a watercraft traveling through water may include a rudder pivotally mounted to the watercraft for steering the watercraft, a fin pivotally mounted to the watercraft substantially along a centerline of the watercraft and forward the rudder, wherein the fin pivots about an upright axis to modify the wake produced by the watercraft traveling through the water, an actuator mounted within the watercraft and operably coupled to the fin for pivoting the fin relative to the centerline, and a controller mounted on the watercraft allowing an operator to control the actuator and selectively pivot the fin to a desired angle θd relative to the centerline.