Crank Assembly

A crank assembly comprising:

• a spindle with a mating feature at each end;
• a first crank arm assembly attached to the spindle's left mating feature, wherein the first crank arm assembly comprises a crank arm, slider assembly, bearing, track, and pedal;
• and
• a second crank arm assembly attached to the spindle's right mating feature, wherein the second crank arm assembly includes a chain ring base, chain ring, bearing, track, crank arm, slider, and pedal;
• and
• wherein the geometry of the track controls the crank assembly collapsing the length of each crank arm assembly from the longest length at about the beginning of the down-stroke, to the shortest length at about the end of the down-stroke of each revolution, and fully extending the crank arm assembly back again to the longest length at about the end of the up-stroke of each revolution.

A crank assembly designed to control the varying length of crank arm assemblies as the crank assembly rotates about a spindle comprising:

• a spindle with a mating feature at each end;
• a first crank arm assembly attached to the spindle's left mating feature, wherein the first crank arm assembly comprises a crank arm, slider, bearing, track, and pedal;
• and
• a second crank arm assembly attached to the spindle's right mating feature, wherein the second crank arm assembly includes a chain ring base, chain ring, bearing, track, crank arm, slider, and pedal.