Patent ID: 7178240

Claim:
A method for molding a bicycle tube comprising the steps of: providing a tube; controlling thickness of said tube by a drawing and extruding process; plasticizing said tube into particular diameters and shapes by plasticizing processes; and hydroforming a selected portion of said tube by a hydroforming device and a mold defining a mold cavity comprising large portions and narrow portions for forming particular three-dimensional shapes, the step of hydroforming said selected portion of said tube comprises the steps of: placing said selected portion of said tube into said mold; injecting pressurized liquid into said tube by said hydroforming device so that said tube is filled with the pressurized liquid; sealing said tube except the communication of the pressurized liquid; pressurizing said pressurized liquid to mold said selected portion of said tube into large portions corresponding to said large portions of said mold cavity; and further pressurizing said pressurized liquid to mold said selected portion of said tube into narrow portions corresponding to said narrow portions of said mold cavity.