The tubular connection of the frame components to be fitted together shall have a minimum length of two times the outside diameter.

连接杆件的管状连接，其最小长度应该是其外径的两倍。

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The water-plugging device of large diameter tube used for water-finding comprises a water-plugging gas bag arranged circulating the frame, an inlet pipe or a discharge pipe is arranged in the frame.

这种大口径管道试水用堵水器的基本结构包括环绕支架设置的堵水 气囊，支架上设置进水管或排气管。

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Even if a stock bike fit me perfectly, no stock bike can change the diameter of the tubes and flex of the frame to suit my whims, but Seven can.

FORBES: Why You Need a Custom Road Bike