A number of variations may include a foldable scooter comprising a first frame component, wherein the first frame component comprises a steering column and a handlebar, wherein the steering column is integrated with an electric drive unit speed controller which is constructed and arranged to operatively control a removeable electric drive module; a second frame component, wherein the second frame component is rotatably attached to the first frame component so that the first frame component can fold onto the second frame component and wherein the second frame component includes a deck; a front wheel operatively connected to the first frame component; and a rear wheel operatively connected to the second frame component.

In a propulsion device including a main wheel having a plurality of driven rollers fitted on and arranged circumferentially along an annular core member so as to be rotatable around tangential lines of the annular core member at respective positions thereof on the annular core member, a pair of drive disks positioned on either side of the main wheel in an individually rotatable manner, a plurality of drive rollers supported along an outer periphery of each drive disk so as to be each rotatable around a rotational center line extending in a skewed relationship to a rotational center line of the corresponding drive disk, and a drive unit for individually rotatively driving the drive disks, a plurality of guide rollers are rotatably supported by a body frame and engage at least one driven roller not engaged by any of the drive rollers from either side.

In a propulsion device including a main wheel having a plurality of driven rollers fitted on and arranged circumferentially along an annular core member so as to be rotatable around tangential lines of the annular core member at respective positions thereof on the annular core member, a pair of drive disks positioned on either side of the main wheel in an individually rotatable manner, a plurality of drive rollers supported along an outer periphery of each drive disk so as to be each rotatable around a rotational center line extending in a skewed relationship to a rotational center line of the corresponding drive disk, and a drive unit for individually rotatively driving the drive disks, a plurality of guide rollers are rotatably supported by a body frame and engage at least one driven roller not engaged by any of the drive rollers from either side.

The power assisting device includes driver with a rotary axis, a main gear, a first transmission rod, a first bevel gear, a second bevel gear, a first rotating rod, a third bevel gear, and a first driving wheel. The main gear is driven by the driver to rotate about the rotary axis. The first transmission rod extends along a direction perpendicular to the rotary axis. The first bevel gear and the second bevel gear are separately sleeved on the transmission rod. The first bevel gear is engaged with the main gear. The first rotating rod extends along a direction parallel to the rotary axis. The third bevel gear is sleeved on the first rotating rod and is engaged with the second bevel gear. The first driving wheel is coupled to the first rotating rod for assisting a wheel of a vehicle to move forward.

The power assisting device includes driver with a rotary axis, a main gear, a first transmission rod, a first bevel gear, a second bevel gear, a first rotating rod, a third bevel gear, and a first driving wheel. The main gear is driven by the driver to rotate about the rotary axis. The first transmission rod extends along a direction perpendicular to the rotary axis. The first bevel gear and the second bevel gear are separately sleeved on the transmission rod. The first bevel gear is engaged with the main gear. The first rotating rod extends along a direction parallel to the rotary axis. The third bevel gear is sleeved on the first rotating rod and is engaged with the second bevel gear. The first driving wheel is coupled to the first rotating rod for assisting a wheel of a vehicle to move forward.

A kit of parts for converting a regular bicycle into an e-bike. The kit includes (i) an electric motive power unit having an external freewheeling sprocket drive assembly configured for demountable engagement with the bike's chain, (ii) a rechargeable battery and battery mount for providing electric power to the electric motive power unit, (iii) a mount bracket for demountably engaging therein the electric motive power unit and for demountably engaging there onto the battery mount, (iv) a power cable with an on/off switch and a demountable handlebar clamp for communication with the electric motive power unit, (v) a throttle control assembly configured for demountable engagement with the bike's handlebar; and (vi) a communication cable engagement with the throttle control assembly and the electric motive power unit and optionally, with a wheel sensor. The kit may additionally comprise a battery charger.