A bicycle seat assembly having an adjustable width nose portion includes an H-shaped base that supports a lateral left side pad and a lateral right side pad. A rail extends under the base and between the left and right side nose portions of the seat assembly. A front rail mount includes a housing, a shuttle, an actuator, and left and right mount supports. Operation of the actuator alters the position of the left and right mount supports relative to the housing and thereby alters a distance between the respective left and right side nose portions of the seat base.