An apparatus for controlling upshifting and downshifting of a bicycle
transmission includes a running condition detecting mechanism that detects
a running condition of the bicycle, a threshold value setting mechanism
that sets at least one of an upshift threshold value and a downshift
threshold value for the running condition, and a control mechanism. The
control mechanism provides a signal that commands at least one of an
upshift and a downshift when the running condition is beyond the
corresponding upshift threshold value and downshift threshold value for a
first predetermined time interval. In another embodiment, the control
mechanism provides a signal that commands at least one of an upshift and a
downshift when the running condition is beyond the corresponding one of
the upshift threshold value and the downshift threshold value at both a
first detection and a second detection, wherein the second detection
occurs after the first detection. The control mechanism provides the
signal after the second detection and not in a time interval between the
first detection and the second detection.
