Disclosed herein is a transmission assembly for a wheeled vehicle. The assembly has a gear box superposed over an existing prior art bicycle. Based on the gear ratios of the gear box, the power input of a rider is increased in the same amount.

The invention disclosures a stage-variation variable speeds transmission bicycle, comprising a bicycle bracket, wherein the bicycle bracket is provided with a medial axis, a medial axis chain wheel group is arranged on the medial axis, medial axis chain wheel group comprises three chain wheels with different size; also comprising bicycle rear shaft, a freehub arranged on rear shaft, the freehub is fixed with a sun gear, one side of the sun gear is provided with a planetary carrier comprising planetary gears, a gear ring is provided radially outward of planetary gears, a ratchet is provided radially outward of the gear ring, the ratchet is provided with a pawl, the invention is easy to start and can be operated at a high speed, also can realize switch between the one-stage and two-stage transmission status arbitrarily during riding and parking to ensure a better cycling experience.

A system and method for simple transmission of a multi-speed bicycle is provided. A bicycle can have a transmission that can be toggled by a kickback shifting mechanism. A rear wheel hub can support a freewheel having a high speed gear sprocket and a low speed gear sprocket with dedicated chains to create dedicated gear-shifting. Rotating the pedal shaft in the non-drive direction approximately one-quarter rotation can toggle the transmission between the first gear ratio and the second gear ratio with a shifting surface that alternately allows driving engagement of the high speed gear sprocket with the rear wheel driver.

A system and method for simple transmission of a multi-speed bicycle is provided. A bicycle can have a transmission that can be toggled by a kickback shifting mechanism. A rear wheel hub can support a freewheel having a high speed gear sprocket and a low speed gear sprocket with dedicated chains to create dedicated gear-shifting. Rotating the pedal shaft in the non-drive direction approximately one-quarter rotation can toggle the transmission between the first gear ratio and the second gear ratio with a shifting surface that alternately allows driving engagement of the high speed gear sprocket with the rear wheel driver.

The present invention relates to an apparatus for providing a pneumatic assist device for a bicycle, wheelchair or other wheeled device. The pneumatic assist device is configured for providing bionic assistance using a pneumatic system. The device further comprises a ball-bearing gear box, a plurality of gears, a bionic assist component, and a pedal assembly. Further, an assist arm engages a gear inside the gear box, and the bionic assist component attaches to a wheel lock, then the pedal assembly has a pump providing pneumatic pressure for a smooth bicycle ride. A plurality of guides align the gears of the gearbox, and a plurality of elastic bands also engage ball-bearings of the gearbox.

A straddle-type vehicle (100) includes a frame (20) and an engine (10) mounted on the frame (20), the engine (10) includes a cylinder head (11) positioned toward the rear end of the frame, and located below a saddle seat (80). The cylinder head laces toward the rear end of the frame, which allows the heated cylinder head of the engine and the exhaust pipe connected to the cylinder head to avoid contact with the vehicle the user's legs while riding the vehicle, so the effect of heat emitted from the cylinder head on the rider's experience is reduced.

A method for shifting a segmented gear may include rotating a gear cluster including a first gear and a coaxial second gear using a power transfer mechanism (e.g., a belt or a chain). The power transfer mechanism defines a plane and is wrapped partially around the first gear. and wherein the first gear has a plurality of gear segments independently movable (e.g., pivotable or translatable) into and out of the plane. A plurality of radially transitionable sliders are rotated in tandem with the first gear, and each of the sliders is operatively coupled to a corresponding one of the gear segments of the first gear. In sequence, each segment of the first gear is moved out of the plane of the power transfer mechanism by urging the slider in a radial direction using a segment actuator, such that the power transfer mechanism wraps at least partially around the second gear.

A bicycle drive includes a multi-sprocket arrangement for rotatable mounting on a rear-wheel axle an engagement with a bicycle chain having inner link plate pairs and chain outer link plate pairs. The multi-sprocket arrangement includes a sprocket having, between an axial inner side and an oppositely situated axial outer side, a flat sprocket body and a plurality of teeth formed on a circumference of the sprocket. The plurality of teeth include at least one tooth of a first tooth group, the axial width of which is dimensioned to be greater than a chain inner link plate spacing and smaller than a chain outer link plate spacing, and a second tooth group, the axial width of which are dimensioned to be smaller than the chain inner link plate spacing.

A bicycle drive includes a multi-sprocket arrangement for rotatable mounting on a rear-wheel axle an engagement with a bicycle chain having inner link plate pairs and chain outer link plate pairs. The multi-sprocket arrangement includes a sprocket having, between an axial inner side and an oppositely situated axial outer side, a flat sprocket body and a plurality of teeth formed on a circumference of the sprocket. The plurality of teeth include at least one tooth of a first tooth group, the axial width of which is dimensioned to be greater than a chain inner link plate spacing and smaller than a chain outer link plate spacing, and a second tooth group, the axial width of which are dimensioned to be smaller than the chain inner link plate spacing.

A bicycle component for an at least partially muscle-powered bicycle with at least one freewheel unit including a freewheel component and a support unit and a spring unit, the freewheel component containing a tubular body section extending around a central axis and configured hollow showing a non-round outer contour for non-rotatable and axially displaceable coupling and a front surface with axial engagement components. The spring unit urges the freewheel component and the support unit apart in an axial direction of the central axis. The freewheel component, the support unit, and the spring unit form an assembly suitable for pre-assembly, and the spring unit is attached to the freewheel component and the support unit.