| 摘要 |
A bike frame comprises a top beam; a head beam; two diagonal down beams; a seat beam; and a bottom bracket shell; said top beam extending between the seat beam and the head beam; and said diagonal down beams extending between said head beam and said bottom bracket shell; said bike frame further comprising a pair of seat stays and a pair of chain stays; said pair of seat stays extending rearwardly from said seat beam and said pair of chain stays extending rearwardly from said bottom bracket shell; wherein said frame comprises composite sheet material of fibre and resin; wherein each one of said pair of diagonal down beams is hollow and incorporates an innermost wall of composite sheet material which is substantially upright and parallel to an innermost wall of composite sheet material of its neighbouring beam. |
