Abstract: A method for manufacturing a bicycle rim includes the following steps. A first bar of material and a second bar of material are formed by extrusion. The first bar and the second bar are respectively made into an arched section of material (unfinished external ring, unfinished internal ring) and cut. Excessive portions of the unfinished external and internal rings are cut from by trimming. The unfinished external and internal rings are assembled and interconnected to each other. The assembled unfinished external and internal rings are laterally pressed to promote a connection between the unfinished external and internal rings. The ends of the unfinished external ring are welded and connected to each other, and the ends of the unfinished internal ring are welded and connected to each other to from a rim structure. Any roughness of the rim structure is ground and the bicycle rim is finished.

Abstract: A rim includes an external ring and an internal ring. The external ring includes two walls each including a brake-contacting face, a middle portion interconnecting the walls, a bead-receiving groove defined by the walls and the intermediate portion, two external flanges extending from the middle portion opposite to the walls, two internal flanges extending from the middle portion opposite to the walls. An edge-receiving groove is defined between each of the external flanges and a related one of the internal flanges. The internal ring includes two walls and an intermediate portion interconnecting the walls. Each of the walls of the internal ring includes an edge inserted in a related one of the edge-receiving grooves, a shoulder abutted against. a related one of the external flanges, and an external side in flush with the brake-contacting face of a related one of the walls of the external ring.

Abstract: A bicycle rim includes a plurality of elongate slots each of which is composed of a first diameter portion and a second diameter portion which is smaller than the first diameter portion. A tube having threaded outer periphery is inserted in each elongate slot and a core piece is inserted through a passage in the tube. The tube has a flange engaged with an inside of the rim and a cover member covering each elongate slot has a threaded hole for being threadedly connected to the threaded outer periphery of the tube. A protrusion extends from a side of the cover member so as to be engaged with the first diameter portion while the tube is shifted to the second diameter portion. A spoke is inserted in the core piece and threadedly connected to a threaded inner periphery of the core piece.