100 in swinging between an upper position to a lower position and a retractable wheel system 86 for traction support and stability the preferred embodiment also preferably further comprises a drive system 70 and a suspension system 50 the linkage system 20 comprises at least one linkage arm and a crank system 60 in the preferred embodiment the linkage system 20 comprises a pair of linkage arms a left linkage arm 14 and a right linkage arm 16 attached to a crank system 60 the left linkage arm 14 and the right linkage arm 16 are essentially mirror images of one another with the exception that the distal end of the lower linkage arm 21 of the right linkage arm 16 is elongated and has a toe kick bar 27 extending perpendicularly both of these differences are more thoroughly described infra the right linkage arm 16 as shown in fig2 comprises a lower linkage arm 21 attached at a proximal end to the distal end of an upper linkage arm 22 at a linkage arm joint pivot 24 in the preferred embodiment the upper linkage arm 22 comprises a pair of opposing arm pieces the lower linkage arm 21 is further attached at a lower linkage pivot 26 to a linkage attachment 38 at or near the center of the lower linkage arm 21 the linkage attachment 38 is part of the swing arm.