A continuously variable transmission for bicycles having a transmission mechanism
including a plurality of link units for converting rotary motion of an input shaft
rotated by a pedal-operated crankshaft into swinging motion, and a one-way clutch
for converting the swinging motion into rotary motion of an output shaft. The link
units have drive links pivotally mounted on an eccentric ring which rotates in
unison with the input shaft. The continuously variable transmission is disposed
between a front wheel and a rear wheel of a bicycle in the longitudinal direction
thereof and disposed either upwardly of a hypothetical plane which contains the
axes of rotation of the front wheel and the rear wheel or upwardly of a position
below and near the hypothetical plane. The transmission so configured provides
better bicycle maneuverability, lower cost, while suffering almost no danger of
contacting the ground.