Abstract: An electric bicycle frame includes a seat tube, a down tube, a top tube, a battery box, and a battery body. The seat tube includes an upper portion and a lower portion. The down tube includes a first end and a second end. The second end is connected to the lower portion. The top tube includes a third end, an expanding tube, and a fourth end. The fourth end is connected to the upper portion. The expanding tube is between the third end and fourth end. The expanding tube includes a tube diameter varying portion and a top opening. The tube diameter varying portion includes continuously varying cross-sections. The battery box is assembled inside the top opening of the expanding tube. The battery body is received in the battery box.

Abstract: An electric bicycle frame includes a seat tube, a down tube, a top tube, a battery box, and a battery body. The seat tube includes an upper portion and a lower portion. The down tube includes a first end and a second end. The second end is connected to the lower portion. The top tube includes a third end, an expanding tube, and a fourth end. The fourth end is connected to the upper portion. The expanding tube is between the third end and fourth end. The expanding tube includes a tube diameter varying portion and a top opening. The tube diameter varying portion includes continuously varying cross-sections. The battery box is assembled inside the top opening of the expanding tube. The battery body is received in the battery box.

Abstract: A two stage quick-release structure includes a first tubing member, a second tubing member, a first pivoting portion, a first buckling portion, an elastic hook and a safety fastener. When the user assembles the foldable bicycle for bicycling, the first tubing member is rotated to connect with the second tubing member via the first pivoting portion, so that the elastic hook correspondingly buckles with the first buckling portion to form a first stage buckle; then, the safety fastener is rotated to correspondingly buckle with the elastic hook so as to form a second stage buckle. The two stage buckle contributes the assembling of the foldable bicycle with ease and convenience. Furthermore, via the two stage buckle structures, the connection between the front bicycle frame body and the rear bicycle frame body are tightly secured.

Abstract: A combination structure of bicycle frame and motor hub includes a bicycle frame, a motor hub, and an elongated axle. One can extend, from one side of the bicycle frame, the elongated axle through a through hole of the bicycle frame and the motor hub, and then with one hand, a tail end of the elongated axle can be fastened into an internal thread hole of the bicycle frame. This will facilitate assembly of the components of the motor hub and the bicycle frame. Besides, when screwing or unscrewing the elongated axle, since the elongated axle has passed through the through hole and the internal thread hole opposing each other at the bicycle frame, the motor hub will not fall accidentally, and convenience can be assured for maintenance staff during proceeding of maintenance work.

Abstract: A two stage quick-release structure includes a first tubing member, a second tubing member, a first pivoting portion, a first buckling portion, an elastic hook and a safety fastener. When the user assembles the foldable bicycle for bicycling, the first tubing member is rotated to connect with the second tubing member via the first pivoting portion, so that the elastic hook correspondingly buckles with the first buckling portion to form a first stage buckle; then, the safety fastener is rotated to correspondingly buckle with the elastic hook so as to form a second stage buckle. The two stage buckle contributes the assembling of the foldable bicycle with ease and convenience. Furthermore, via the two stage buckle structures, the connection between the front bicycle frame body and the rear bicycle frame body are tightly secured.

Abstract: A combination structure of bicycle frame and motor hub includes a bicycle frame, a motor hub, and an elongated axle. One can extend, from one side of the bicycle frame, the elongated axle through a through hole of the bicycle frame and the motor hub, and then with one hand, a tail end of the elongated axle can be fastened into an internal thread hole of the bicycle frame. This will facilitate assembly of the components of the motor hub and the bicycle frame. Besides, when screwing or unscrewing the elongated axle, since the elongated axle has passed through the through hole and the internal thread hole opposing each other at the bicycle frame, the motor hub will not fall accidentally, and convenience can be assured for maintenance staff during proceeding of maintenance work.