Patent ID: 6994367

Claim:
A composite bicycle frame of a first metal subassembly and a second fiber reinforced plastic composite subassembly comprising: the first metal subassembly being a metal spine having a head portion, a main tube, a bottom bracket portion and chain stays, said chain stays terminating in dropouts; said head portion has a rearwardly projecting cylinder; said bottom bracket portion has an upwardly projecting cylindrical receptacle; said dropouts have upwardly and forwardly projecting cylindrical receptacles extending therefrom; said fiber reinforced plastic composite subassembly having a fiber reinforced plastic composite seat tube, top tube, and seat stay assembly; said composite seat tube, top tube, and seat stay being joined at a seat lug portion; said seat lug portion being received in and bonded to said top tube; said composite seat tube being received in and bonded to said bottom bracket receptacle; said top tube being received in and bonded to said head tube receptacle, and said seat stay assembly being received in and bonded to said dropout receptacles; said spine is formed of welded titanium or welded titanium alloy; said composite seat tube spanning the greater portion of the distance between said top tube and said bottom bracket receptacle; said bottom bracket receptacle having a width and a length in which said length is between two and three times the width; said top tube spanning the greater portion of the distance between said seat tube and said head tube; said head tube receptacle having a width and a length in which said length is between two and three times the width; said seat stay assembly spanning the greater portion of the distance between said dropout and the intersection of said seat tube and top tube; said dropout receptacle having a width and a length in which said length is between two and five times the width; said seat tube and said seat lug portion being formed as a unitary structure of fiber reinforced plastic, said second fiber reinforced plastic composite subassembly is formed entirely of fiber reinforced plastic tubes with an integral seat lug portion.