A rear drive transmission system for a motorcycle includes a driving wheel, a center wheel, and a driven wheel. The center wheel includes a transmission wheel A and a transmission wheel B that are coaxially arranged. The transmission wheel A is fixedly connected to an opposite surface of the transmission wheel B. The driving wheel is drivingly connected to the transmission wheel B. The transmission wheel A is drivingly connected to the driven wheel, and the driving wheel is detachably and fixedly connected to an output shaft of a motor or engine. The driven wheel is detachably connected with a rear wheel shaft of the motorcycle. The center wheel is rotatably connected with a rear fork rotation center shaft through a bearing. The motorcycle is with the motorcycle rear drive transmission system.

A bicycle includes a frame having a seat tube, a rear wheel including a drive plate, and a drive system configured to drive rotation of the rear wheel. The drive system includes at least one shaft operably extending in a direction between the seat tube and the rear wheel and arranged to interact with the drive plate. A pair of drive assemblies are located near or at least in part inside the seat tube and are arranged to operably interact with the drive shaft. The at least one drive shaft converts linear motion of the drive assemblies into rotation of the rear wheel without a chain or chainring.

A negative pressure air suction type fluid-driven power machine comprises a fluid pressure accumulation bin, a necking port, a flow inlet, a flow guiding cover, a fluid-inlet flow guiding cover, turbine driving blades, a turbine housing, a turbine shaft, a turbine bracket, nozzles surrounding peripheries of the turbine driving blades, a turbine fluid outlet, a fluid negative-pressure flow guiding cover, a fluid negative-pressure outlet, an external driving fluid inlet, an external driving fluid flow guiding cover, and nozzles. The negative pressure air suction type fluid-driven power machine is formed using a gravity acceleration fluid generated by a fluid flowing to a direction opposite to operation of an object as a main driving power source and using a fluid air suction phenomenon as an auxiliary power source, and can replace some effects of steam engines, internal combustion engines, motors and the like.

A negative pressure air suction type fluid-driven power machine comprises a fluid pressure accumulation bin, a necking port, a flow inlet, a flow guiding cover, a fluid-inlet flow guiding cover, turbine driving blades, a turbine housing, a turbine shaft, a turbine bracket, nozzles surrounding peripheries of the turbine driving blades, a turbine fluid outlet, a fluid negative-pressure flow guiding cover, a fluid negative-pressure outlet, an external driving fluid inlet, an external driving fluid flow guiding cover, and nozzles. The negative pressure air suction type fluid-driven power machine is formed using a gravity acceleration fluid generated by a fluid flowing to a direction opposite to operation of an object as a main driving power source and using a fluid air suction phenomenon as an auxiliary power source, and can replace some effects of steam engines, internal combustion engines, motors and the like.

Traction systems for skis producing traction on snow and ice covered surfaces; the skis selected from a group consisting a pair of Back Country skis each are mounted with an apparatus; having DC powered controls, tilt switch, pressurized carbon dioxide (CO.sub.2) gas powered pneumatic actuators operating gripping parts; controlled by a servo unit. And further consisting a pair of snowmobile skis each having an assembly of parts; driven by an hydraulic rotor that pivots the skis, adjusting their position when cornering, providing traction, according to a snowmobile steering system. And is powered and controlled by at least one of: hydraulic steering system, an electro-hydraulic steering system; an electric power steering system using an electric motor instead of hydraulic rotor.