Abstract: A bicycle of the "mountain bike" type having two aligned foldable joints in the frame, a folding handlebar assembly and a foldable pedal. Each of the frame joints is mounted in a gap in a tubular frame member and includes two disks disposed flushly against the ends of the tubular members with smaller plugs fast in the members, and two hinge leaves extending across the gap longitudinally of the frame. A rivet on one side of the joint joins two ears on the leaves to form the hinge axis, and a headed fastener with a hexagonal socket is recessed into the thickened central portion of the upper leaf and threaded into the lower leaf to clamp the leaves together. Interlocking ribs between two ears on the other side of the joint prevent relative pivoting movement when the leaves are clamped together. The handlebar assembly has upper and lower tubular adjustment sections for both upward and forward adjustment of the handlebar, and an angled hinge between these sections.

Abstract: A stem is fixed to a head tube of a bicycle by a fixing device. The stem has an aperture formed in a center. A hole is formed in an upper end of the vertical tube for receiving a spring and a bolt. Two holes are laterally and oppositely formed in a lower portion of the stem, and each receives a piston. The aperture and the holes are filled with oil. The pistons are pushed to engage with an inner surface of the head tube when the bolt is threaded into the upper hole so that the stem can be firmly fixed to the head tube.

Abstract: An attachment for the horsehead of an oil well pump jack or pumping unit including a pair of strap assemblies oriented in spaced, generally parallel relation to each other with each strap assembly including two components hingedly connected to each other with each strap component including means adjustably securing it to the opposite sides of the horsehead with such means also enabling detachable connection between either of the strap components and the horsehead so that the attachment may be used for various purposes during repair, maintenance and the like and also serve as a retaining device for the wire line assembly which extends from the wire line hanger at the upper corner of the horsehead to the polished rod.