A human mobility device, comprising: a frame; a seat configured to support a human; a plurality of wheels (48, 49) connected to said frame; a transmission connected to said frame and at least one of said plurality of wheels (48, 49); at least one lever (41, 103) connected to said frame and to said transmission; said lever (41, 103) being shiftable between: a first mode of operation in which movement of said lever in a first direction causes said transmission to drive at least one of said plurality of wheels (48, 49) in a first direction, so as to propel said human mobility device forward; a second mode of operation in which movement of said lever in a second direction causes said transmission to drive at least one of said plurality of wheels (48, 49) in a second direction, so as to propel said human mobility device backward; characterized in that said transmission further comprises a first drive shaft (2, 302) connected to said lever (41, 103) and said first drive shaft (2, 302) being axially movable through a first plurality of one-way clutch bearings (3, 4, 10, 20, 30, 40, 220, 230) by moving said lever (41, 103) generally to a left or right relative to a person sitting in and facing forward in said human mobility device; wherein said first drive shaft (2, 302) comprises one or more areas having a first diameter and one or more areas having a second diameter that is smaller than said first diameter; said first diameter sized to engage and clutch an internal diameter of each of said first plurality of one-way clutch bearings (3, 4, 10, 20, 30, 40, 220, 230); and said second diameter sized to disengage and be released from said internal diameter of each of said first plurality of one-way clutch bearings (3, 4, 10, 20, 30, 40, 220, 230). a frame; a seat configured to support a human; a plurality of wheels (48, 49) connected to said frame; a transmission connected to said frame and at least one of said plurality of wheels (48, 49); at least one lever (41, 103) connected to said frame and to said transmission; said lever (41, 103) being shiftable between: a first mode of operation in which movement of said lever in a first direction causes said transmission to drive at least one of said plurality of wheels (48, 49) in a first direction, so as to propel said human mobility device forward; a second mode of operation in which movement of said lever in a second direction causes said transmission to drive at least one of said plurality of wheels (48, 49) in a second direction, so as to propel said human mobility device backward; characterized in that said transmission further comprises a first drive shaft (2, 302) connected to said lever (41, 103) and said first drive shaft (2, 302) being axially movable through a first plurality of one-way clutch bearings (3, 4, 10, 20, 30, 40, 220, 230) by moving said lever (41, 103) generally to a left or right relative to a person sitting in and facing forward in said human mobility device; wherein said first drive shaft (2, 302) comprises one or more areas having a first diameter and one or more areas having a second diameter that is smaller than said first diameter; a first mode of operation in which movement of said lever in a first direction causes said transmission to drive at least one of said plurality of wheels (48, 49) in a first direction, so as to propel said human mobility device forward; a second mode of operation in which movement of said lever in a second direction causes said transmission to drive at least one of said plurality of wheels (48, 49) in a second direction, so as to propel said human mobility device backward; characterized in that said transmission further comprises a first drive shaft (2, 302) connected to said lever (41, 103) and said first drive shaft (2, 302) being axially movable through a first plurality of one-way clutch bearings (3, 4, 10, 20, 30, 40, 220, 230) by moving said lever (41, 103) generally to a left or right relative to a person sitting in and facing forward in said human mobility device; wherein said first drive shaft (2, 302) comprises one or more areas having a first diameter and one or more areas having a second diameter that is smaller than said first diameter; said first diameter sized to engage and clutch an internal diameter of each of said first plurality of one-way clutch bearings (3, 4, 10, 20, 30, 40, 220, 230); and said second diameter sized to disengage and be released from said internal diameter of each of said first plurality of one-way clutch bearings (3, 4, 10, 20, 30, 40, 220, 230).