Abstract: A derailleur includes a linkage mechanism including a fixing member, a chain guide having an inner guide plate and an outer guide plate generally parallel to one another, and a linkage device supported to the fixing member and movable axially relative to the front chain gear assembly. The inner guide plate includes an elongate urging portion on its inner side surface closest to the outer guide plate. The urging portion is swollen in a direction toward the outer guide plate and is provided to contact the driving chain to urge it when the chain guide is moved to shift the driving chain. The inner guide plate has a first mounting device positioned above the urging portion and another mounting device positioned below the urging portion. The linkage device is connected to the inner guide plate at both the mounting devices.

Abstract: The derailleur includes a linkage mechanism comprising a fixing member fixed to the bicycle frame, a pair of linkage members pivoted to the fixing member, and a movable member carrying a chain guide and pivoted to the linkage members. The linkage mechanism is provided with a displacement structure which elastically biases the linkage mechanism axially of a multistage sprocket assembly when subjected to a force or pressure greater than a normal resistance against speed change, thereby preventing the fixing member and bicycle frame from being plastically deformed as a result of a sudden forceful impact, such as in a collision, hitting a foreign object of if the bicycle falls down.

Abstract: A bicycle derailleur which includes a linkage mechanism formed of a base member, an inner linkage member, an outer linkage member, and a movable member carrying a chain guide. The derailleur also includes a connecting assembly formed of a pair of connecting pins for respectively pivotably supporting one end of each of the inner and outer linkage members to the base member and a pair of connecting pins for respectively pivotably supporting the movable member to the other end of each of the inner and outer linkage members. The connecting pins are oriented obliquely with respect to a predetermined plane perpendicular to the axis of the sprocket assembly. The chain guide, responsive to deformation of the linkage mechanism, moves axially and radially of the sprocket assembly.

Abstract: The method includes providing an aluminum plate having an outer peripheral portion in an elliptic shape, the outer peripheral portion including a plurality of tooth portions. An intermediate element is formed by pressing the aluminum plate to cause the outer peripheral portion of the plate to project unidirectionally in a thickness direction with respect to a radially inward portion of the intermediate element to form a flange at the outer peripheral portion. The plurality of tooth portions are formed at this flange. A plurality of teeth members are formed by cutting the flange of the intermediate element in a thickness direction thereof at an outer surface in a projecting direction of the flange to reduce the thickness of the flange relative to the thickness of the intermediate element.

Abstract: A bicycle pedal having a pedal shaft and a pedal body, the pedal body being made from synthetic resin and integral with a main body. The main body has bearings and foot bearing members having foot bearing surfaces, so that the foot bearing members are supported such that they are elastically displaceable with respect to the main body to thereby absorb shocks occuring during pedalling.

Abstract: The derailleur is provided with a base member; a linkage mechanism including a support member, a pair of linkage members, and a movable member; and a chain guide having a guide sprocket and a tension sprocket. The support member is supported swingably relative to the base member through a first horizontal shaft, and the chain guide is supported swingably relative to the movable member through a second horizontal shaft. Also, first and second springs are provided between the base member and the linkage mechanism, and the movable member and the chain guide. The first and second springs balance with each other to set the position of the guide sprocket with respect to a selected particular rear chain gear. The spring force of at least one of the first and second springs is changed with respect to the other by the swinging motion of at least one of the linkage mechanism and the chain guide in excess of a predetermined angle, thereby yielding an optimum distance between the guide sprocket and the rear chain gear.

Abstract: The device is provided with a positioning mechanism having a positioning member, a switching mechanism for switching the positioning mechanism from an operating mode thereof to a non-operating mode and a friction mechanism for applying a resistance to rotation of the lever body when the positioning mechanism is switched to the non-operating mode. Gaps are provided between the positioning member and the lever body, whereby the positioning member is adapted to follow the rotation of the lever body with a predetermined delay when the positioning member is in the operating mode. When the positioning mechanism is switched to the non-operating mode, the positioning member follows the rotation of the lever body without delay because the rotational idling of the positioning member caused by the gaps is eliminated.

Abstract: The derailleur body is swingably supported to a fixing member through a first horizontal shaft and chain guide is swingably supported to a movable member at the derailleur body through a second horizontal shaft. A first spring and a second spring balance with each other to set a guide sprocket of the chain guide in position with respect to a desired one of multistage chain gears. A stopper plate is rotatably supported to and first horizontal shaft a retains one end of the first spring. The stopper plate includes an adjusting means which changes the position of the stopper plate with respect to an abutting projection at the fixing member to thereby adjust a twist angle of the first spring.

Abstract: A mounting structure for mounting a bicycle part, such as a front derailleur, to a bicycle frame using a band member. The band member is wound around the bicycle frame and has a pair of mounting legs each having an engaging bore therein. The bicycle part to be mounted includes a base member which includes a receiving bore for the mounting legs. The inner wall of the receiving bore includes cam faces for pushing the mounting legs together as the mounting legs are inserted into the receiving bore to reduce the distance between the mounting legs. A screw tightening member is supported rotatably to the base member and screws with a nut having engaging projections which engage with the engaging bores in the mounting legs when the mounting legs have been inserted a sufficient distance into the receiving bore such that the distance between the mounting legs is less than the distance between the tips of the engaging projections on the nut.

Abstract: A freewheel for a bicycle having an annular space formed between a cylindrical driving member carrying sprockets and a cylindrical driven member and between a pair of bearings supporting the driving member rotatably with respect to the driven member. The annular space is closed by sealing rings, and the driving member is provided with an oil feeding conduit which is open at one end into the annular space and at the other end outwardly from the driving member.

Abstract: A support structure for supporting a chain guide to a movable member of a bicycle derailleur. The support structure includes a support shaft and a locking member which swingably supports the chain guide to the movable member and prevents it from coming loose therefrom. The movable member is provided with a cylindrical portion having a bottom wall with a shaft bore and also having a cover member which is integral with the movable member. The cover member has a cavity formed outwardly of the bottom wall. The cavity receives the utmost end of the support shaft projecting from the bottom wall. The cover member has an insertion bore through which the locking member is inserted to engage with a retaining groove of the support shaft.

Abstract: A derailleur for a bicycle having a derailleur body having a base member, a movable member having a chain guide, and a support means for supporting the movable member movably axially of a multistage sprocket assembly with respect to the base member; and a control cable for movably controlling the movable member, whereby an amount of movement of the chain guide in the axial direction of a multistage sprocket assembly is made adjustable with respect to a constant control amount of the control cable.

Abstract: A rear derailleur for a bicycle having a linkage mechanism supported swingably to a fixing member through a first horizontal shaft, a first spring interposed between the linkage mechanism and the fixing member, and a second spring interposed between a movable member at the linkage mechanism and a chain guide, so that the first and second springs balance with each other to allow the linkage mechanism and chain guide to swing, thereby controlling a guide pulley at the chain guide in position with respect to each sprocket at the multistage sprocket assembly. Hence, even when the position to support an operating wire for the linkage mechanism during the swinging motion thereof varies to vary the position of the guide pulley with respect to the multistage sprocket assembly, an interval between the chain and the urging surface therefor is held constant.

Abstract: A brake operating device for a bicycle in which an operating lever is pivotally supported to a bracket shaped generally like a right prism and having at its rear portion an opening which opens rearwardly. The outer surface of the bracket includes a bracket cover which covers the bracket. A restraint member is provided which restrains the bracket cover from moving with respect to the bracket. The restraint member is coupled with either the bracket or the operating lever and is retained to the edge portion of the bracket cover covering the opening at the bracket.

Abstract: A bicycle caliper brake is provided which includes a pair of brake arms each having a brake shoe on one end thereof. A support bolt supports the brake arms rotatably relative to each other. The brake arms each have a boss with a throughbore by which the brake arms are fitted onto the bolt. The bosses are supported on the bolt adjacent to each other. A thrust bearing is interposed between opposite surfaces of the bosses, and a sealing element is disposed at an outer periphery of the thrust bearing between the opposite surfaces of the bosses.

Abstract: A speed change hub for a bicycle includes a driving member, a ring gear rotatable in association with the driving member and having first transmitting members for transmitting a driving force to a hub shell, and a gear frame having planetary gears engageable with inner teeth of the ring gear. The hub also includes a sun gear disposed on a hub shell and having second transmitting members for transmitting the driving force to the hub shell, and a relay member rotatable in association with the driving member. The relay member includes third transmitting members for transmitting the driving force to the gear frame, is supported axially slidably to the hub shaft, and has a first clutch for controlling the first transmitting members to engage or disengage from the hub shell. The hub shaft axially slidably supports an actuator in operative engagement with an operating rod and has a second clutch for controlling the third transmitting members to engage or disengage from a gear frame.

Abstract: A derailleur for a bicycle is provided with a base member, a movable member movable axially of a multistage sprocket assembly, a linkage member for moving the movable member axially of the multistage sprocket assembly, a guide mechanism supported to the movable member and guiding a driving chain from one sprocket to another at the multistage sprocket assembly, and a coiled return spring. At an intermediate portion of the linkage member there is a provided a support shaft for the spring, with the support shaft supporting the coiled portion of the spring. A first end portion of the spring is retained to the linkage member carrying the support shaft, and a second end portion of the spring is movably engaged with a member movable relative to the linkage member, thereby reducing the amount of deflection of the spring for a given amount of movement of the movable member.

Abstract: A rear bicycle derailleur is provided which includes (1) a chain guide formed of a guide pulley, a tension pulley and first and second plates supporting the guide and tension pulleys, and (2) a derailleur body having a movable member supporting the chain guide and support means supporting the movable member to be movable axially of the multistage sprocket assembly. The first plate includes a first restrainer at a side of the first plate adjacent the derailleur body, with the first restrainer being positioned radially outwardly relative to the guide pulley at a location outside a first predetermined chain movement path along which the chain travels from a high speed sprocket of the multistage sprocket assembly to the tension pulley through the guide pulley when the multistage sprocket assembly rotates in reverse. The first restrainer prevents the chain from moving away from the first chain movement path when the multistage sprocket assembly rotates in reverse.

Abstract: A bicycle derailleur which includes a linkage mechanism formed of a base member, two linkage members and a movable member carrying a chain guide. A swingable member is pivotally supported to one of two opposite members of the linkage mechanism. A return spring is supported to the other of these two opposite members and a first leg of the return spring is retained to the swingable member, while a second leg thereof is retained to the other of the aforesaid two opposite members of the linkage mechanism. A control wire is pulled to move the movable member in a forward direction with respect to the base member and the return spring restores the movable member to a rest position, thereby changing the bicycle speed. A variation in an angle of torsion of the spring is reduced with respect to a variation in the forward stroke of the movable member, whereby operating forces at the top gear side and the low gear side of the multistage gear assembly are substantially equalized to each other.

Abstract: A bicycle derailleur is provided which has a pair of linkage members interposed between a base and a movable member. At least one of the linkage members is connected to a least one of the base member and the movable member such that one of (i) the at least one linkage member and (ii) the aforesaid at least one of the base member and the movable member comprises an insertion region having a pair of mounting walls and the other of (i) the at least one linkage member and (ii) the aforesaid at least one of the base member and the movable member comprises an insertion portion inserted between the mounting walls. A link pin is disposed between the mounting walls and passes through the insertion portion. One of (i) both the mounting walls and (ii) opposite surfaces of the insertion portion opposite to the mounting walls includes an annular recess surrounding the link pin. A sealing member is disposed in each annular recess to prevent water, mud, and debris from entering into a space surrounding the link pin.