Abstract: A head set positioning device includes a positioning tube having a rack portion defined in an outer periphery thereof and the position tube movably extends through a crown portion of a front fork and is fixedly connected to a lower head set which is connected to a lower end of the head tube. An upper head set is fixedly connected to an upper end of the head tube and a handlebar stem is mounted to the positioning tube. An extension tube extends from the handlebar stem and a gear member is rotatably received in the extension tube and is engaged with the rack portion. The handlebar stem is pulled to press the upper head set by rotating the gear member.