Abstract: A height adjustment assembly for a bicycle saddle includes an inner tube with a saddle clamp on the top thereof. A retractable device is located in the inner tube and is fixed to the saddle clamp. The inner tube is movably inserted into an outer tube. A control device is located in the outer tube and includes a top part, a block and an operation unit. The top part is fixed to the retractable device and the switch of the retractable device extends through the top part and activates an operation unit received in the block. The operation unit is activated by a cable so as to move the switch of the retractable device to adjust the height of the saddle.

Abstract: An adjustable handlebar stem assembly includes a vertical tube with a head which has a toothed face. A stem includes two plates which are pivotably connected to the head and includes a clamping portion to clamp a handlebar thereto. A pawl member is pivotably located between the two plates and includes press end and an engaging portion on two ends thereof. The engaging portion has teeth removably engaged with the toothed face. A restriction rod extends through one of the two plates and is connected to a restriction member. A quick-release is pivotably engaged with a curved and recessed face of the pawl member. The quick-release includes a recess with which the restriction member is engaged. The quick-release cannot be pivoted when the restriction member is not moved and disengaged from the recess of the quick-release, so that the stem is not pivoted relative to the vertical tube.

Abstract: An anti-theft device for bicycle seat post includes a restriction member connected to the bottom end of the seat post. The restriction member has a disk extending from the outer periphery thereof, and the disk protrudes radially from outer periphery of the bottom end of the seat post. A fastening member is be connected to the top end of the seat tube and the seat post extends through the passage. A first stepped portion and a second stepped portion are respectively defined in the inner periphery of the passage. The first stepped portion is rested on the top end of the seat tube. When the seat post is lifted to its maximum position, the disk of the restriction member is engaged with the second stepped portion so that the seat post cannot be pulled out from the seat tube.

Abstract: A bicycle seat adjustment device includes an inner tube which is inserted into a seat post. The bicycle seat is connected to the top end of the inner tube. The seat post is movably inserted into the upper portion of an outer tube, and the retractable portion of the inner tube is located in the lower portion of the outer tube. An operation unit is connected to the bottom end of the outer tube and controls the movement of the inner tube.

Abstract: A saddle mounting device includes a support member having a mounting portion formed thereon. A lower base is connected with the support member. The lower base has two guiding flanges diametrically formed thereon. Two gaps are respectively defined between the two guiding flanges. The lower base has two first engaging grooves defined therein. An upper base is movably connected with the lower base. The upper base has two sliding rods formed thereon for sliding along the two guiding flanges and are guided into the two gaps. The upper base has two second engaging grooves defined therein for corresponding to the two first engaging grooves. A fastener connects the support member with the lower base and is screwed with the upper base. The upper base is simultaneously moved relative to the lower base by a rotation of the fastener.

Abstract: A saddle mounting device includes a support member having a mounting portion formed thereon. A lower base is connected with the support member. The lower base has two guiding flanges diametrically formed thereon. Two gaps are respectively defined between the two guiding flanges. The lower base has two first engaging grooves defined therein. An upper base is movably connected with the lower base. The upper base has two sliding rods formed thereon for sliding along the two guiding flanges and are guided into the two gaps. The upper base has two second engaging grooves defined therein for corresponding to the two first engaging grooves. A fastener connects the support member with the lower base and is screwed with the upper base. The upper base is simultaneously moved relative to the lower base by a rotation of the fastener.

Abstract: A seat post assembly includes a saddle positioning unit adapted to be mounted to a saddle. An outer tube has one end connected to the saddle positioning unit. An inner tube is received in the outer tube. An opening laterally defined in an outer periphery of the inner tube. An inner post passes through the inner tube and is received in the outer tube. The inner post has a recess laterally defined in one end thereof. An abutting member is disposed in the recess and protrudes from the opening in the inner tube for contacting with an inner peripheral wall of the outer tube. A tightening unit radially passes through the outer tube, the inner tube, and the inner post for pushing the abutting member to abut against the inner peripheral wall of the outer tube for refraining the inner tube from rotating relative to the outer tube.

Abstract: A skate cart includes a board with a front wheel and a rear wheel. A handlebar stem is pivotally connected to a connection port extending from a front end of the board and the front wheel is connected to the handlebar stem. The connection port has two lugs and a lower end of the handlebar stem is engaged between the two lugs. A rod is movably inserted through one of the lugs and a passage in the handlebar stem. When pulling the rod out from the passage in the handlebar stem, the handlebar stem is pivotable relative to the board.

Abstract: A shock absorbing seat post structure for a bicycle includes a seat post having a lug defining a pivot hole and an opening located under the pivot hole, a fixed rod mounted in the opening, a supporting base pivotally mounted to the lug and having a front end defining a first receiving space and a rear end pivotally mounted to the pivot hole and defining a second receiving space, a shoulder formed in the supporting base and defining a through hole, an adjusting rod having a front end passing through the through hole of the shoulder and a rear end mounted to the fixed rod, an annular shoulder mounted on the adjusting rod, and an elastic tube having a front end urged on the shoulder of the supporting base and a rear end urged on the annular shoulder of the adjusting rod.

Abstract: A pivotable seat structure for a bicycle includes a seat post having a block formed on the top thereof, a positioning post passing through the rear end of the block, an abutting flange formed on the block, and an elastic pad mounted on the middle of the block, an inverted U-shaped supporting bracket defining a receiving space for receiving the block and having a front end pivotally mounted on the front end of the block and a rear end defining an sector slot, an inverted V-shaped driver having a front end formed with a hook detachably urged on the positioning post and a rear end passing through the sector slot and formed with a press block, a torsion spring having a front end abutting the front end of the driver for forcing the hook to urge on the positioning post, and a rear end urged on the bottom of the supporting bracket, and a seat fixedly mounted on the supporting bracket.

Abstract: A seat assembly includes a seat tube in which a seat post is movably received therein which has a clamping member with a seat disposed thereto. The seat post has two plain portions defined diametrically opposite in an outer periphery thereof and the seat tube has two wedge-shaped recesses defined diametrically opposite in an inner periphery thereof so as to receive two wedge-shaped blocks therein. The seat post extends through a nut member which is threadedly mounted to the seat tube.

Abstract: A device for adjusting positions of a bicycle's handlebar is engaged to a steerer tube and includes a base element and a pivotal element which receives the handlebar therein, the base element is securely engaged to the steerer tube, the pivotal element has a second hole defined transversely therein for receiving a rod therein and two slots defined in a toothed under surface of the pivotal element, which communicate with the second hole, the base element has two fourth holes defined therein and a toothed surface defined in an upper surface thereof for the toothed surface of the pivotal element to engage with the threaded surface of the base element and two bolts extend through the fourth holes, the two slots and to threadedly engage with threaded holes defined in the rod received in the second hole such that the handlebar and the pivotal element can be pivoted corresponding to an axis of the rod.

Abstract: A seat adjusting device is disposed on a seat post which has a rounded top and has a third hole and a second slot respectively and transversely defined therein, a base having an upper part and two plates extending from the upper part, each of the two plates having a first hole and a first slot defined therein so as to receive the rounded top of the seat post between the two plates wherein the first slot and the second slot have an opposite slope with each other so as to define an overlap portion, a pin extending through the first hole and the third hole, a first bolt extending through the overlap portion of the first and the slots and engaging to a nut, a mounting element mounting to the upper part and being securely engaged to the upper part by a second bolt engaging therebetween.

Abstract: A cushion assembly for a bicycle seat includes a tubular member securely mounted to a bicycle seat tube, a seat post partially received in the tubular member and having an upper end to which a bicycle seat is attached, a spring received in the tubular member and having an upper end on which the seat post rests and a lower end abutting against a bottom of the tubular member, a bolt extending from an outside of the bottom of the tubular member through the receptacle to engage with the seat post to move therewith, thereby allowing vertical movements of the seat post in the tubular member. First and second clamp plates are mounted between the tubular member and the seat post and each have a contour complimentary to that of an outer periphery of the seat post, thereby preventing relative rotational movements between the seat post and the tubular member. The tubular member has a plurality of holes defined in a periphery thereof, providing an access to the second clamp plate.

Abstract: A quick release for a bicycle includes a handle portion which has two ears extending from one end thereof such that a space is defined between the two ears, a pin pivotally engaged between the two ears of the handle portion, a bolt having a first end fixed to the pin between the two ears of the handle portion and a second threaded end, a nut threadedly engaged with the second end of the bolt, a gasket mounted around the bolt and movably abutting against the two ears of the handle portion, the improvement comprising: the bolt having an extension portion which extends from the second threaded end thereof and is hexagonal in section; the pin having a first end and a second end which are hexagonal in section and respectively extend outwards of the two ears of the handle portion; and the handle portion having a plurality of hexagonal slots defined in a mediate portion thereof and having a plurality of rectangular openings defined in a peripheral portion thereof.

Abstract: A pivot arm assembly secures a handlebar to a steerer tube and includes a shank having a sleeve for engaging with the steerer tube. The shank has a lateral aperture communicating with the cylindrical opening of the sleeve. Two clampers and a fastener are engaged in the aperture. The clampers each includes a tapered surface for engaging with the tapered surfaces of the fastener so as to force the fastener to engage with the steerer tube when the clampers are forced toward each other. The fastener has an embossed surface for solidly engaging with the steerer tube.

Abstract: An engaging device for securing a handlebar stem of a bicycle includes a handlebar stem which has vertical and level portions, the level portion having an opening formed in a side wall of the level portion and communicating to an interior of the vertical portion, the vertical portion being a tubular element for receiving an upper end of a front fork therein. A main tapered element and two side tapered elements are disposed in the level portion through the opening, the main tapered element having a recess formed in a rear end thereof for engaging with the front fork and having a slant formed on lateral sides thereof, the side tapered element having a slant corresponding to that of the main tapered element. The main tapered element is forced to push toward the front fork with the recess by the side tapered elements when threading the bolt.

Abstract: A quick release clamp includes a handle pivotally fixed on a U-shaped bracket via a pin. The U-shaped bracket has a central hole at a base therein and two plates integrally and perpendicularly extended from two sides of the base. A bolt device having a head portion and a rod portion is threadedly engaged with a nut by a lower end of the rod portion with the rod penetrating the hole of the U-shaped bracket and the head portion being slidably received in the U-shaped bracket. A transverse hole is formed in the head portion of the bolt device for receiving a middle portion of the pin. The pin has a recess formed at a middle portion thereof suitable to receive a peripheral portion of the transverse hole of the head portion of the bolt device. The pin is rotatable in concert with the handle thus allowing the bracket to be manually moved close to or away from the nut.