Abstract: The invention solves the issue of stiff mounting of a wheel to a bicycle frame. The essential feature of the invention is that in the seating nests of the axle are bulges and hollows with slanting surfaces. The outer contour of the axle's wall section, which is parallel to the wheel symmetry plane which goes through the slanting surface, has a non-circular shape, preferably the shape of a regular polygon or similar to a regular polygon or an irregular polygon or the shape of an irregular closed curve.

Abstract: A frame unit for a two-wheeled vehicle may comprise a main frame. The main frame may be formed by a first partial shell and a second partial shell that is joined to the first partial shell. The first partial shell and the second partial shell may be produced from a material comprising steel. The main frame may further comprise an upper tube, a lower tube, a seat tube, and/or a head tube. A rear section may be joined to the main frame and may include a chain stay and/or a seat stay. Further, each of the first and second partial shells may form a lateral half of the main frame, and the first and second partial shells may have a C-shaped cross section. The frame unit avoids the disadvantages of the prior art and offers a high degree of design freedom.

Abstract: A bicycle crank assembly has a sprocket, a first crank arm, a second crank arm and a crank axle, A first axial distance is defined between the first pedal attachment surface and the second pedal attachment surface in an axial direction. A second axial distance is defined between the first transverse center plane of the sprocket and the second axial center plane of the crank axle in the axial direction. The first axial distance is smaller than or equal to 170 mm. The second axial distance is larger than or equal to 55 mm.

Abstract: A sprocket includes a sprocket body, first and second teeth alternatively arranged radially around an outer periphery of the sprocket body, a driving and a non-driving sides respectively defined on the first and second teeth in the driving direction and the non-driving direction, a recess defined between each first tooth and one adjacent second tooth, the first and second teeth each having a first or second tooth tip, a first groove and a second groove respectively extended from sprocket body to the first tooth tips of each two adjacent first teeth and form a thickness of said first teeth, that said first teeth is axially wider than said second teeth. Each first tooth includes two first front chamfers respectively disposed on the said first tooth flank of said two opposite radial surfaces and located on the intersection of said drive side of said each first tooth and said first and second grooves of said sprocket body.

Abstract: A connecting device for a chainring of a bicycle is disclosed, including a connecting disc, a shaft, and a crank. The connecting disc is adapted to be engaged with a chainring, and has an axial bore, a bulging portion bulging from a central portion of the connecting disc, and a surrounding portion, which is flat, and surrounds an outer periphery of the bulging portion. The shaft passes through the axial bore to be fixedly engaged with the connecting disc. The shaft has a connecting end. The crank has a connecting end engaged with the connecting end of the shaft, and a bearing end adapted to bear an external force to make the crank rotate around the shaft. Whereby, the amount of materials used to make the connecting device is decreased. At the same time, the manufacturing cost, the size, and the weight of the connecting device are all reduced.

Abstract: A bicycle front sprocket comprises a sprocket body and at least one sprocket tooth. The sprocket body includes a crank arm mounting portion including a first mounting axial surface facing toward an axial bicycle-center plane in an axial direction in a state where the bicycle front sprocket is mounted to the bicycle frame. The at least one sprocket tooth has a first chain-engagement axial surface facing toward the axial bicycle-center plane in the axial direction in a state where the bicycle front sprocket is mounted to the bicycle frame. The first chain-engagement axial surface is offset from the first mounting axial surface toward the axial bicycle-center plane in the axial direction. An axial distance is defined from the first mounting axial surface to the first chain-engagement axial surface in the axial direction and is equal to or larger than 6 mm.

Abstract: A right crank arm assembly for a bicycle has a right crank arm and at least one toothed crown that is coupled to the right crank arm. At least one damping element is arranged between the right crank arm and the toothed crown to be in abutment against respective faces of the right crank arm and the toothed crown.

Abstract: A right crank arm assembly for a bicycle, comprises a right crank arm and at least one front sprocket coupled with the crank arm at at least one coupling portion of the crank arm. The front sprocket has an inner side adapted, in use, to face towards the frame of the bicycle and an outer side opposite the inner side. The assembly comprises at least one first crank arm element which acts in contact with the front sprocket on one of said sides and at least one second crank arm element which acts in contact with the front sprocket on the other of said sides. The contact action of the crank arm elements on the two opposite sides of the front sprocket prevents the twisting deformation of the front sprocket during pedaling. Such a deformation would cause a reduction in the transmission efficiency of the right crank arm assembly.

Abstract: A transport apparatus including a drive; a first arm connected to the drive, where the first arm includes a first link, a second link and an end effector connected in series with the drive, where the first link and the second link have different effective lengths; and a system for limiting rotation of the end effector relative to the second link to provide substantially only straight movement of the end effector relative to the drive when the first arm is extended or retracted.

Abstract: A bicycle bottom bracket assembly having a rotational central axis includes a support member, a bearing unit and a radially inward force reducing structure. The support member includes a hanger mounting portion and a bearing mounting portion. The bearing mounting portion is configured to be at least partly positioned within a hanger part of a bicycle frame. The bearing unit includes an outer race, an inner race and at least one roller element disposed between the outer and inner races in a radial direction with respect to the rotational central axis. The outer race is fixed to the bearing mounting portion of the support member. The radially inward force reducing structure reduces a radially inward force being transmitted to the bearing unit.

Abstract: A cycle with tapered drivetrain connections. The cycle includes a frame, a crank rotatably connected to the frame, and a driven wheel rotatably connected to the frame. The crank includes a crank arm and a crank spindle rotatably connected to the frame and non-rotatably connected to the crank arm. The crank spindle includes a crank mating surface to interface with the crank arm. The diameter of the crank spindle continuously decreases along at least a portion of the crank mating surface in a lateral direction. The crank arm includes a crank bore to interface with the crank mating surface. At least a portion of the crank bore has a diameter that continuously decreases in lateral direction. At least a portion of the crank bore taper has a taper rate and diameter equal to a taper rate and diameter of at least a portion of the crank spindle taper.

Abstract: A bicycle pedal unit comprises a central body (2) associable with a tube of a bicycle frame; two pedal cranks (3, 4) connected to opposite ends (2a) of the central body (2); two pedals (5, 6), each connected to a respective pedal crank (3, 4); the angular position of at least a movable pedal crank (3) is adjustable relative to the other pedal crank (4), which is fixed.

Abstract: A right crank arm assembly for a bicycle, comprises a right crank arm, a first annular element directly coupled with said crank arm at at least one first coupling portion of said first annular element and at least one second annular element coupled with said crank arm and of a smaller size than said first annular element. The first annular element comprises a toothing that extends radially towards the outside along a primitive circumference having a predetermined diameter. Said at least one first coupling portion is entirely contained in a first area extending radially towards the outside starting from an ideal circumference having a diameter at least equal to ? of said predetermined diameter. Such an annular element constitutes the front sprocket of the crank arm assembly of the present invention and consists of a simple toothed band. Such a front sprocket is particularly light in weight.

Abstract: A crank system of the present disclosure has a first crank assembly that is coupled to a first end of a first axle and coupled to a first pedal. The crank system further has a second crank assembly coupled to a second end of the first axle and a second pedal. Additionally, the crank system has a rotating wheel fixedly coupled to the first crank assembly and the second crank assembly such that as the first and second pedals are actuated by a user, the rotating wheel rotates thereby actuating a chain and inducing motion in a vehicle.

Abstract: A crank system of the present disclosure has a rotating bar that is fixedly coupled to a first end of a first axle and for actuating a wheel, a first crank assembly coupled to the first end of the first axle and coupled to a first pedal, and a second crank assembly coupled to a second end of the first axle and a second pedal. The first crank assembly and the second crank assembly are coupled to the first axle such that the rotating bar is aligned with a wheel gear assembly adapted for rotating the wheel when the first pedal and second pedal are at their zenith and nadir positions, alternatively.

Abstract: A bicycle sprocket is provided that includes an external peripheral edge part and an internal peripheral edge part. The external peripheral edge part has a plurality of metal sprocket teeth. The internal peripheral edge part is positioned radially inward of the external peripheral edge part. The internal peripheral edge part is integrally formed as a one-piece unit with the external peripheral edge part. The internal peripheral edge part has at least one recess that extends radially outward from an inner edge of the internal peripheral edge part toward the external peripheral edge part.

Abstract: A dual-drive hub device is mounted on a rear wheel of a bicycle and has a hub, a main shaft mounted through the hub, and two rear pedals connected to the main shaft. At least one one-way bearing is tightly fitted between the hub and the main shaft. A rear transmission wheel of a transmission system of the bicycle is mounted around the hub. When two front pedals of the bicycle are pedaled, the hub and the rear wheel rotate accordingly. When the rear pedals are pedaled, the main shaft, the hub and the rear wheel rotate accordingly. Thus, a rider and a passenger can pedal the front pedals and the rear pedals simultaneously and enjoy ease of bicycle pooling.

Abstract: A crank assembly of a shaft driven bicycle includes a crank arm pivoted to an axis of a bicycle frame for arranging pedal. The crank arm has at least one main transmission gear to be engaged with a passive gear of a passive shaft. Teeth of the main transmission gear face opposite to the crank arm. The main transmission gear of the crank assembly won't interfere with the axis of the bicycle, and the main transmission gear is driven directly by the crank arms for better power transmission efficiency.

Abstract: A bicycle crank arm and chainring carrier assembly. The assembly includes a crank arm. A chainring carrier is sized and shaped to connect to the crank arm. A first pairing feature is formed on one of the crank arm and the chainring carrier and a second pairing feature is formed on the other of the crank arm and the chainring carrier to position the chainring carrier on the crank arm. A clearance is defined between the first and second pairing features when the first and second pairing features are paired. A torque-transmitting coupling between the crank arm and the chainring carrier is configured to transmit substantially all of the torque applied to the chainring carrier from the crank arm.

Abstract: A bicycle front sprocket has a sprocket body and a chain engagement structure. The sprocket body has a center rotational axis, a first side surface and a second side surface. The second side surface is a smaller sprocket facing side. The chain engagement structure is disposed on an outer periphery of the sprocket body. The chain engagement structure includes a plurality of sprocket teeth extending radially outward from the outer periphery of the sprocket body. The sprocket teeth include at least one first tooth having a first tooth top with a first leading edge and a first trailing edge. The first leading edge is positioned downstream from the first trailing edge with respect to the driving-rotational direction of the bicycle sprocket. The first tooth top is shaped so that the first leading edge is positioned closer to the first side surface than the first trailing edge in the axial direction.

Abstract: A drive mechanism (20) including a first shaft (324) having a first fixed gear (328) and a second shaft (322) having second fixed gear (330) that engages the first fixed gear to cause the first shaft to rotate in an opposite direction than the second shaft. A first linkage (368) connecting the first shaft and the third shaft and includes a first one-way gear (336). A second linkage (366) connecting the second shaft and the third shaft and includes a second one-way gear (338). The third shaft outputs a unidirectional rotational motion.

Abstract: A bicycle crank assembly is basically provided with a crank axle, a first outer shell member, a second outer shell member, a first crank axle supporting member and a second crank axle supporting member. The crank axle has an end portion with an external mounting surface and an internal mounting surface. The first and second outer shell members are arranged relative to each other with a space being formed between the first and second outer shell members. The first crank axle supporting member is disposed on the first outer shell member and supports the external mounting surface of the crank axle. The second crank axle supporting member is disposed on the first outer shell member and supports the internal mounting surface of the crank axle.

Abstract: In a sprocket for a bicycle having a radial bearing acting as a bearing portion, an axial load acting on the bearing can be easily adjusted without having to dismount the components of the bicycle after the bicycle has been assembled. An elastomer is used as a component for an anti-rotation mechanism of an adjusting nut which serves to adjust the axial load of the radial bearing, so that an excessive load is not applied on the radial bearing, which would result in a defective rotation. Further, the axial load acting on the radial bearing can be easily adjusted without having to dismount the components of the bicycle after the bicycle has been assembled.

Abstract: Crank arm spider adjustment orientation system to provide different angular orientations in the attachment of at least an ovoid chainring, comprising an ovoid chainring (3) and a spider (1), both of them provided with multiple anchorage points (30, 10) arranged as holes distributed along the perimeter of a BCD, and mechanical anchorage means (5) engaging chainring anchorage points (30) with corresponding spider anchorage points (10); where the number of said spider anchorage points (10) is multiple of and greater than the number of said mechanical anchorage means (5), and the angular increment between consecutive chainring's (3) orientations provided by the chainring anchorage points (30) is different than the angular increment between consecutive chainring's (3) orientations provided by the spider anchorage points (10), so the combination of the spider (1) with at least one ovoid chainring (3) multiplies the possibilities for said ovoid chainring's (3) orientation reducing the angular increment between conse

Abstract: A crankset and bottom bracket assembly for a bicycle having a spindle. The crankset and bottom bracket assembly comprising a first crank. The first crank comprising a first ratchet mechanism configured for connection to the spindle at a first end. Wherein when the first ratchet mechanism is rotated in a first direction relative to the spindle, the pawl does not engage the tooth and the first crank freewheels relative to the spindle, and wherein when the first ratchet mechanism is rotated in a second direction relative to the spindle, the pawl engages the tooth and rotation of the first crank drives the rotation of the spindle.

Abstract: A first sprocket is capable of engaging with a chain. The first sprocket has a first sprocket main body, a plurality of teeth disposed along a circumferential direction on the radially outer side of the first sprocket main body, and at least one shifting area. The teeth include at least one first tooth having a first maximum axial width and at least one second tooth having a second maximum axial width. The first maximum axial width is greater than the second maximum axial width. The first tooth is formed to be capable of engaging with an outer link plate of the chain. The second tooth is formed to be capable of engaging with an inner link plate of the chain.

Abstract: A composite bicycle component includes a first member made of a metallic material. The first member has a surface with a first dimple. The first dimple includes a second dimple that is formed on the first dimple. Preferably, the composite bicycle component further includes a second member attached to the first member so that a part of the second member extends into the first and second dimples.

Abstract: The present invention is directed to a device for synchronously actuating at least two independent controlled apparatuses at two sides of the bottom bracket of the bicycle through a driving process. The independent controlled apparatuses can be foldable pedals or quick-disassembling pedals or foldable cranks.

Abstract: A bearing preload adjuster for a bicycle crank set and bottom bracket comprises an adjustment ring for coupling with a bicycle crank arm, a movable plunger comprising an external thread for rotatably coupling with the adjustment ring. The adjustment ring is rotated in order to cause the plunger to extend along an axis of the bottom bracket and apply pressure to a bottom bracket bearing inner race. The adjustment ring is rotated until the clearance in the bearing assemblies and the play in the bottom bracket assembly has been eliminated. This allows the crank assembly to rotate freely, while preventing the crank assembly from sliding side to side inside the bearing bores and along the axis of the crank spindle.

Abstract: A bicycle crankset including a first crank and a second crank, and a spider that secures at least one chain ring to the crankset Each of the first crank and the second crank has an end adapted to engage a pedal. The crankset also includes a spindle extending between and engaged with the first crank and the second crank. The spindle includes a radially extending arm and a protrusion disposed on the arm, and the arm co-molded with the spider to transmit torque to the spider.

Abstract: A bottom bracket, which has a shaft, a first pedal crank, which is connected in a rotationally fixed manner to the shaft, a second pedal crank, which is connected in a rotationally fixed manner to the shaft, and a chainring carrier, which is connected to the shaft. The object of providing a bottom bracket with a chainring carrier that is easy to assemble is achieved by the chainring carrier being connected in a rotationally fixed manner to a chainring shaft and by the chainring shaft being connected in a rotationally fixed manner to the shaft.

Abstract: A bicycle front sprocket has a sprocket body and a chain engagement structure. The sprocket body has a center rotational axis, a first side surface and a second side surface. The second side surface is a smaller sprocket facing side. The chain engagement structure is disposed on an outer periphery of the sprocket body. The chain engagement structure includes a plurality of sprocket teeth extending radially outward from the outer periphery of the sprocket body. The sprocket teeth include at least one first tooth having a first tooth top with a first leading edge and a first trailing edge. The first leading edge is positioned downstream from the first trailing edge with respect to the driving-rotational direction of the bicycle sprocket. The first tooth top is shaped so that the first leading edge is positioned closer to the first side surface than the first trailing edge in the axial direction.

Abstract: A bicycle crank assembly is provided that basically provided with a crank arm that includes a first outer shell, a second outer shell, a first axle supporting member and a second axle supporting member. The first and second outer shells are adhesively attached together to form an interior cavity. The first axle supporting member is disposed at the first axle attachment end of the first outer shell. The first axle supporting member has a first bore with a first splined inner surface at least partially disposed in the interior cavity. The second axle supporting member is disposed at the second axle attachment end of the second outer shell. The second axle supporting member has a second bore with a second splined inner surface aligned with the first splined inner surface of the first bore and at least partially disposed in the interior cavity.

Abstract: A bicycle crank set is comprising a crank having at least one support portion protruding therefrom, a first lateral surface, a second lateral surface opposite to the first lateral surface; a first chain wheel located at the first lateral surface and having a second through hole; a second chain wheel located at the second lateral surface and having at least one threaded hole; and a screw bolt inserted outward through the second through hole and then the first through hole to be engaged with the threaded hole. Accordingly, the bicycle crank set is structurally simple and convenient in assembly and the head of the screw bolt is hidden at the inner side of the crank set to be aesthetic in appearance.

Abstract: A connecting and adjusting structure for a crank assembly used in a bicycle contains a first tube of a first connector including a first hollow portion, the first connector including a first bearing seat to receive a first ball bearing, the first bearing seat includes a first engaging tab, a first adjusting rib, and the first tube, a second connector including a second bearing seat to receive a second ball bearing, a dustproof cover, and a retaining ring, the second bearing seat including a second engaging tab, a second adjusting rib, and a second tube, a second crank including a central shank with plural T-shaped teeth and second internal screws, a first crank including a hollow post with a Tee groove fixed to engage with the T-shaped teeth, and a screw is inserted through the hollow post to be screwed with the second internal screws.

Abstract: A right crank arm assembly for a bicycle, comprises a right crank arm and at least one front sprocket coupled with the crank arm at at least one coupling portion of the crank arm. The front sprocket has an inner side adapted, in use, to face towards the frame of the bicycle and an outer side opposite the inner side. The assembly comprises at least one first crank arm element which acts in contact with the front sprocket on one of said sides and at least one second crank arm element which acts in contact with the front sprocket on the other of said sides. The contact action of the crank arm elements on the two opposite sides of the front sprocket prevents the twisting deformation of the front sprocket during pedaling. Such a deformation would cause a reduction in the transmission efficiency of the right crank arm assembly.

Abstract: A right crank arm assembly for a bicycle, comprises a right crank arm, a first annular element directly coupled with said crank arm at least one first coupling portion of said first annular element and at least one second annular element coupled with said crank arm and of a smaller size than said first annular element. The first annular element comprises a toothing that extends radially towards the outside along a primitive circumference having a predetermined diameter. Said at least one first coupling portion is entirely contained in a first area extending radially towards the outside starting from an ideal circumference having a diameter at least equal to ? of said predetermined diameter. Such an annular element constitutes the front sprocket of the crank arm assembly of the present invention and consists of a simple toothed band. Such a front sprocket is particularly light in weight.

Abstract: A crankset for a bicycle that includes a first crank, a second crank, a spindle, a bearing, and a preload mechanism. Each of the first crank and the second crank has an end adapted to engage a pedal. The spindle defines an axis and includes a first end that is coupled to the first crank and a second end that is coupled to the second crank. The bearing positioned around the spindle between the first crank and the second crank to permit rotation of the spindle. The preload mechanism is coupled to the spindle between the bearing and the first crank. The preload mechanism includes a washer that extends circumferentially around the spindle and a cam member that is engageable with the washer to move the washer along the axis to preload the bearing.

Abstract: A right crank arm assembly for a bicycle has a right crank arm and at least one toothed crown that is coupled to the right crank arm. At least one damping element is arranged between the right crank arm and the toothed crown to be in abutment against respective faces of the right crank arm and the toothed crown.

Abstract: Provided is a pedal force sensor which, in pedal force detection utilizing an elastic body, can detect pedal force over a wide range and reduce detection errors originating from variation in the attachment position or length etc. of the elastic body. Linkage between a drive wheel (30) that is fixed to a crankshaft (14) and a sprocket (50) that transmits rotary force of the crankshaft (14) to a propelling vehicle wheel is effected by a plurality of springs (80 to 90), and furthermore the space between each spring (80 to 90) and compression means thereof is set in such a way that the compression commencement timings of the plurality of springs (80 to 90) are offset. When detecting pedal force from the phase difference of the drive wheel (30) and the sprocket (50), the number of springs that are utilized changes in accordance with the range of the phase difference.

Abstract: A device for disassembling and assembling bicycle pedals comprises a bicycle crank (1), detachable pedals (17) connected with the crank (1), a fixing seat (11) arranged at an end of the crank (1), a control device arranged at the fixing seat (11) and a connection assembly between a pedal (17) and the control device. The control device also comprises an unlocking mechanism, a pushing mechanism and a rotating mechanism, wherein the pushing mechanism and the rotating mechanism are controlled by a gear mechanism. The device can conveniently and quickly disassembling and assembling bicycle pedals by one step without touching the pedals with hands.

Abstract: A right crank arm assembly for a bicycle, comprises a right crank arm and at least one front sprocket coupled with the crank arm at least one coupling portion of the crank arm. The front sprocket has an inner side adapted, in use, to face towards the frame of the bicycle and an outer side opposite the inner side. The assembly comprises at least one first crank arm element which acts in contact with the front sprocket on one of said sides and at least one second crank arm element which acts in contact with the front sprocket on the other of said sides. The contact action of the crank arm elements on the two opposite sides of the front sprocket prevents the twisting deformation of the front sprocket during pedaling. Such a deformation would cause a reduction in the transmission efficiency of the right crank arm assembly.

Abstract: A solitary chainring of a bicycle front crankset for engaging a drive chain, including a plurality of teeth formed about a periphery of the chainring, the plurality of teeth consisting of an even number. The plurality of teeth includes a first group of teeth and a second group of teeth arranged alternatingly between the first group of teeth. The first group of teeth and the second group of teeth are equal in number. Each of the first and second group of teeth include an outboard side and an inboard side opposite the outboard side and each tooth of the first group of teeth includes at least a first protrusion on the outboard side thereof and each tooth of the second group of teeth are free of the first protrusions on the outboard side and the inboard side.

Abstract: A cartridge bottom bracket is for a bicycle having a tubular shell with a bore. The bottom bracket includes a spindle having opposing ends and a sealed cartridge disposed within the shell bore and about a central portion of the spindle so as to define opposing free end portions of the spindle. The cartridge includes a pipe having opposing ends, two rolling contact bearings disposed within the pipe adjacent to a separate one of the pipe ends and rotatably coupling the spindle with the pipe, and a tubular spacer disposed about the spindle and extending between the two bearings so as to establish a spacing distance between the bearings. Further, two shaped caps are each mounted on a separate one of the free end portions of the spindle and are disposed axially against a separate one of the bearings to enclose the free end portion of the spindle.

Abstract: A crank assembly for an acrobatic bicycle includes a mandrel, two cranks, a chainwheel, and a connector. The chainwheel has a shaft hole and a fixing hole. The connector has a mounting hole and a locking hole connected with the shaft hole and the fixing hole respectively. The mounting hole has a mounting portion inserted into the shaft hole. The mounting hole has an engaging surface. The mandrel has two urging portions, and one of the urging portions is extended through the mounting hole and is engaged with the engaging surface. Thus, the connector is connected with the chainwheel and located between the chainwheel, the mandrel and one of the cranks to enhance the structural strength of combination of the chainwheel, the mandrel and the two cranks.

Abstract: Double crank alternating cycle traction system in which two independent free-turning cranks with a dynamic articulation at the place where the force is applied are strategically added to a conventional pedal cycle. The operation of the resulting mechanical composition increases the mechanical advantage of the original system. The invention is applicable to pedal cycles, mainly all kinds of bicycles, i.e. bicycles, tricycles, four-wheeled bicycles, moved by the extremities of the human body, i.e. the hands or feet.

Abstract: A bicycle crank assembly is provided with a first sprocket, a second sprocket, a crank arm, a sprocket fixing structure and an alignment tube. The first sprocket includes a plurality of first teeth and at least one first mounting portion having a first mounting opening. The second sprocket includes a plurality of second teeth and at least one second mounting portion having a second mounting opening. The crank arm includes at least one sprocket attachment portion having a third mounting opening. The sprocket fixing structure secures the first and second sprockets to the crank arm via the first, second and third mounting openings. The alignment tube extends through at least two of the first, second and third mounting openings.

Abstract: A bicycle sprocket is provided that includes an external peripheral edge part and an internal peripheral edge part. The external peripheral edge part has a plurality of metal sprocket teeth. The internal peripheral edge part is positioned radially inward of the external peripheral edge part. The internal peripheral edge part is integrally formed as a one-piece unit with the external peripheral edge part. The internal peripheral edge part has at least one recess that extends radially outward from an inner edge of the internal peripheral edge part toward the external peripheral edge part.

Abstract: A bicycle transmission system is provided herein. The bicycle transmission system includes a sprocket or ring that is capable of sliding amongst an infinite number of lateral positions relative to a crank arm. The movement of the sprocket or ring facilitates an optimal chain path from the sprocket or ring to another sprocket or ring in the transmission system and, therefore, increases the efficiency with which power is transferred through the system.

Abstract: The present invention relates to a mechanical element, and more particularly, to a crank connected to a bicycle pedal or a handle for rotating a rotary body and to a bicycle using the same. The present invention uses a cylindrical cam, an end cam, or a swash plate cam, and the shafts of these cams and a shaft of a pedal or a handle for applying force are equipped with a miter gear (a bevel gear the number of teeth of which is 1:1 and the shaft angle of which is 90 degrees), such that the crank retracts/extends one time per one rotation of the pedal or the handle.