A prone bicycle comprising a frame (1), a front wheel (2), a rear wheel (3), a drive mechanism (4) for driving the rear wheel (3), and a pedal mechanism (5) for driving the drive mechanism (4), in which, the front wheel (2) and rear wheel (3) are mounted on the front portion and rear portion of the frame (1), wherein: a forearm support member (6) is mounted at the frame (1) front portion, and a dynamic knee support member (7) having synchronous movement with the pedal mechanism (5) is mounted between the pedal mechanism (5) and the frame (1). Designed with multi-point dynamic and static supports, this prone bicycle improves riding comfort and efficiency and is combined with crawling fitness function.

A crankset for a bicycle comprising a shaft rotationally engaged with a bicycle frame, the shaft having a radially extending flange disposed toward one end, a first crank arm and a second crank arm, and each connected to an opposing end of the shaft and being approximately 180 degrees out of phase with each other, a first sprocket keyed to the shaft, the first sprocket having a toothed belt engaging surface, and a spacer member disposed between the first sprocket and the flange for adjusting a first sprocket position.

A crankset for a bicycle comprising a shaft rotationally engaged with a bicycle frame, the shaft having a radially extending flange disposed toward one end, a first crank arm and a second crank arm, and each connected to an opposing end of the shaft and being approximately 180 degrees out of phase with each other, a first sprocket keyed to the shaft, the first sprocket having a toothed belt engaging surface, and a spacer member disposed between the first sprocket and the flange for adjusting a first sprocket position.

A bicycle is provided that can include front and rear wheels; a handle bar; and top, bottom, head, front seat, and rear seat tube members (each with a longitudinal axis) that form a frame that is suspended between the wheels. A distance between the head tube member and the front seat tube member can be 14 inches or less. The distance can also be one-half or less of the distance between the head tube member and the rear seat tube member. The longitudinal axis of the head tube member can intersect a longitudinal axis of the front seat tube member at 120 inches or less above a riding surface. The rotational planes of the front pedals of a front crankset can overlap a rotational plane of the front wheel. The handle bar rotates about a volume representative of an upper body of a front rider and/or cargo.

A bicycle is provided that can include front and rear wheels; a handle bar; and top, bottom, head, front seat, and rear seat tube members (each with a longitudinal axis) that form a frame that is suspended between the wheels. A distance between the head tube member and the front seat tube member can be 14 inches or less. The distance can also be one-half or less of the distance between the head tube member and the rear seat tube member. The longitudinal axis of the head tube member can intersect a longitudinal axis of the front seat tube member at 120 inches or less above a riding surface. The rotational planes of the front pedals of a front crankset can overlap a rotational plane of the front wheel. The handle bar rotates about a volume representative of an upper body of a front rider and/or cargo.

The present disclosure related to an effort-saving crank structure (1) of a bicycle (8), which includes: a crank mechanism (10) having a crank (11), a shaft end gear (12) and a treadle end gear (13) disposed on the crank (11); a transmission mechanism (20) disposed in the crank (11) and having a rotation shaft (21) and a first gear (22) and a second gear (23) connected to the rotation shaft (21), the first gear (22) and the shaft end gear (12) are engaged for transmission, and the second gear (23) and the treadle end gear (13) are engaged for transmission; a rotation arm unit (30) having a first rotation arm (31) and a second rotation arm (32), two ends of the second rotation arm (32) are respectively connected to the first rotation arm (31) and the treadle end gear (13).

The present disclosure related to an effort-saving crank structure (1) of a bicycle (8), which includes: a crank mechanism (10) having a crank (11), a shaft end gear (12) and a treadle end gear (13) disposed on the crank (11); a transmission mechanism (20) disposed in the crank (11) and having a rotation shaft (21) and a first gear (22) and a second gear (23) connected to the rotation shaft (21), the first gear (22) and the shaft end gear (12) are engaged for transmission, and the second gear (23) and the treadle end gear (13) are engaged for transmission; a rotation arm unit (30) having a first rotation arm (31) and a second rotation arm (32), two ends of the second rotation arm (32) are respectively connected to the first rotation arm (31) and the treadle end gear (13).

A gear mechanism is provided, having a gear arrangement, and a spindle arrangement to support the gear arrangement, the spindle arrangement having first, second, third and fourth spindles. The gear arrangement, of concentric gears only, that includes a first gear set mounted on the first and fourth spindles and arranged to be driven via a first pedal, a second gear set mounted on the second and fourth spindles and arranged to be driven via a second pedal, and a third gear set mounted on the third and fourth spindles, wherein, for each of the first and second gear sets, the gear set is configured to be alternately driven, via the corresponding pedal being rotated through less than 180°, in a power stroke to drive the third gear set, and, advanced, via the corresponding pedal being rotated through more than 180°, in a return stroke to commence a subsequent power stroke.

A gear mechanism is provided, having a gear arrangement, and a spindle arrangement to support the gear arrangement, the spindle arrangement having first, second, third and fourth spindles. The gear arrangement, of concentric gears only, that includes a first gear set mounted on the first and fourth spindles and arranged to be driven via a first pedal, a second gear set mounted on the second and fourth spindles and arranged to be driven via a second pedal, and a third gear set mounted on the third and fourth spindles, wherein, for each of the first and second gear sets, the gear set is configured to be alternately driven, via the corresponding pedal being rotated through less than 180°, in a power stroke to drive the third gear set, and, advanced, via the corresponding pedal being rotated through more than 180°, in a return stroke to commence a subsequent power stroke.

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.