Abstract: A bicycle head structure includes a stem and a detachable cover. The stem is disposed between a handlebar and a head tube of a bicycle, and the stem has a top surface. The detachable cover covers the top surface, and an accommodating space is formed between the top surface and the detachable cover.

Abstract: An adjustable spacer structure of a bicycle is used for adjusting a height of a stem disposed on a steering tube. The adjustable spacer structure includes a first spacer and a second spacer. The first spacer includes a body and a positioning portion. The body has a ring shape and a first opening, and the steering tube is movably disposed through the first opening. The positioning portion is disposed on the body. The second spacer has a ring shape and a combining portion. The combining portion is detachably connected to the positioning portion, and there is a second opening formed between the first spacer and the second spacer. The stem is abutted against the first spacer.

Abstract: A handlebar structure of bicycle suited for being assembled to a stem of a bicycle is provided. The handlebar structure includes a body and a reinforcement member. The body has a first segment fixed to the stem, a second segment, and a third segment held by a rider, wherein the second segment is connected between the first and the third segments. One portion of the reinforcement member is fixed to the stem, and another portion of the reinforcement member is disposed on the second segment. A two-dimensional Cartesian system x-y based on an orthogonal cross-section of the second segment is constructed, and a scope of the second segment being covered by the reinforcement member contains at least a second quadrant of the two-dimensional Cartesian system x-y, wherein the bicycle moves in a positive x-axis direction of the two-dimensional Cartesian system x-y.

Abstract: A bicycle head structure includes a stem and a detachable cover. The stem is disposed between a handlebar and a head tube of a bicycle, and the stem has a top surface. The detachable cover covers the top surface, and an accommodating space is formed between the top surface and the detachable cover.

Abstract: A handlebar structure of bicycle suited for being assembled to a stem of a bicycle is provided. The handlebar structure includes a body and a reinforcement member. The body has a first segment fixed to the stem, a second segment, and a third segment held by a rider, wherein the second segment is connected between the first and the third segments. One portion of the reinforcement member is fixed to the stem, and another portion of the reinforcement member is disposed on the second segment. A two-dimensional Cartesian system x-y based on an orthogonal cross-section of the second segment is constructed, and a scope of the second segment being covered by the reinforcement member contains at least a second quadrant of the two-dimensional Cartesian system x-y, wherein the bicycle moves in a positive x-axis direction of the two-dimensional Cartesian system x-y.

Abstract: An adjustable spacer structure of a bicycle is used for adjusting a height of a stem disposed on a steering tube. The adjustable spacer structure includes a first spacer and a second spacer. The first spacer includes a body and a positioning portion. The body has a ring shape and a first opening, and the steering tube is movably disposed through the first opening. The positioning portion is disposed on the body. The second spacer has a ring shape and a combining portion. The combining portion is detachably connected to the positioning portion, and there is a second opening formed between the first spacer and the second spacer. The stem is abutted against the first spacer.

Abstract: A positioning device includes a mount secured on a seat tube, and left and right joint members having joint surfaces which abut against the mount, and gripping cavities which mate with clamping cavities of left and right clamping members to permit lengthwise segments of left and right anchoring bars of a seat to be clamped in left and right bar-engaging zones, respectively. When the joint surfaces switch places or when the left and right clamping members are shifted, the bar-engaging zones are displaced from a first position to be proximate to corresponding ones of front and rear ends of the anchoring bars, to a second position to be proximate to the other corresponding ones of the front and rear ends of the anchoring bars, thereby enabling the seat to be adjusted to a desired position relative to the seat tube.

Abstract: A suspension system may include a front frame connected to a front wheel, a shock absorber pivotally connected to the front frame, and a rear frame connected to a rear wheel supported by a ground contact point. The shock absorber may include a preset pressure substantially equal to a pressure caused by a body weight of a rider. The suspension system may be structurally configured to maintain an instantaneous center point of movement of the rear frame relative to the front frame within an angle range of about 45°±15° relative to the ground contact point when the rear frame moves relative to the front frame.

Abstract: An aerodynamically configured handlebar assembly for use in a bicycle includes a mounting head which has a rear clamping body for clamping an upper end of a steering stem of a bicycle front fork so as to cantilever a front aerodynamic body of the mounting head, a handlebar body which extends laterally from opposite sides of the front aerodynamic body and which has handgrips at leftmost and rightmost ends thereof, and an aerodynamic bracket member which is disposed beneath the front aerodynamic body and which has a rear crosspiece. The crosspiece is secured to a crotch segment of the bicycle front fork by a fastening unit so as to enable the bracket member to better support weight of the cantilevered front aerodynamic body.

Abstract: A positioning device includes a mount secured on a seat tube, and left and right joint members having joint surfaces which abut against the mount, and gripping cavities which mate with clamping cavities of left and right clamping members to permit lengthwise segments of left and right anchoring bars of a seat to be clamped in left and right bar-engaging zones, respectively. When the joint surfaces switch places or when the left and right clamping members are shifted, the bar-engaging zones are displaced from a first position to be proximate to corresponding ones of front and rear ends of the anchoring bars, to a second position to be proximate to the other corresponding ones of the front and rear ends of the anchoring bars, thereby enabling the seat to be adjusted to a desired position relative to the seat tube.

Abstract: A suspension system may include a front frame connected to a front wheel, a shock absorber pivotally connected to the front frame, and a rear frame connected to a rear wheel supported by a ground contact point. The shock absorber may include a preset pressure substantially equal to a pressure caused by a body weight of a rider. The suspension system may be structurally configured to maintain an instantaneous center point of movement of the rear frame relative to the front frame within an angle range of about 45°±15° relative to the ground contact point when the rear frame moves relative to the front frame.

Abstract: A bicycle frame apparatus is disclosed that includes a main frame, a sub-frame and a shock absorber. The sub-frame moves relative to the main frame. The shock absorber is positioned between the main frame and sub-frame so that the shock absorber effects movement of the sub-frame relative to the main frame. The main frame includes a down tube. The down tube includes an aperture. The shock absorber extends into and/or through the aperture to a connection point that, in some embodiments, is below the down tube.