Patent ID: 8678417

Claim:
A universal frame for electric bikes and human powered bicycles, a frame body of the universal frame is consisted of a top tube, a down tube, a seat tube, two seat stays and two chain stays, a holder is welded on a junction of the down tube, the seat tube and the chain stays, the holder is used to fasten on a bottom bracket shell with different specifications according to usage requirements, wherein: the holder, an outer surface of a top is provided for connecting to the top tube, the down tube and the seat tube of the frame body, an inner hole is set on the outer surface, multiple first locking holes are set on a circumference of the inner hole, a capacity space is set concavely inside the holder for assembling the bottom bracket shell; the bottom bracket shell, which is provided for assembling a main-shaft-chain wheel set, an upper tube flange set on a top of a shell body is set into the inner hole, two side tube flanges are set on two sides of the shell body respectively, the side tube flanges have a side through-hole, an upper through-hole is set on the upper tube flange, multiple second locking holes are set near a circumference of the upper tube flange, the second locking holes are corresponding to the first locking holes of the holder for corresponding first locking bolts locking in, to thereby fasten the bottom bracket shell and the holder; wherein a rear cavity is set on a rear side of the holder, two first rear convex parts are respectively adjacent to two sides of the rear cavity, a first side hole is laterally set on the rear convex part, an inner side of the first rear convex part has a second concave cambered surface.