Patent ID: 8510950

Claim:
A method for making a rear hub of a bicycle comprising the following steps: swaging a straight pipe with a mold into an hour-glass-shaped semi product; after swaging, extruding the semi-product with a mold to form a hub flange at either end of the semi-product; after extruding, punching a plurality of holes in the hub flange of the semi-product, and the holes are annularly arranged; after punching, binding an edge of an end of the semi-product to make the end of the semi-product expand outwards, forming a flared end; after binding, necking down the flared end of the semi-product to make this end constant in diameter; after necking, trimming both ends of the semi-product to a predetermined value; and after trimming, chamfering the holes of the semi-product to form a chamfer structure on an edge of the respective holes.