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Whether upshifting or downshifting, the bicycle derailleur system design requires that the drive chain be
moving forward and be under at least some tension. A derailleur will shift only if you are pedaling forward.
1) Shifting the Rear Derailleur
The rear derailleur is controlled by the right shifter. The function of the rear derailleur is to move the drive chain from one gear
to another on the rear gear cluster, thereby changing gear drive ratios. The smaller sprockets on the gear cluster produce
higher gear ratios. Pedaling in the higher gears requires greater pedaling effort, but takes you a greater distance with each
revolution of the pedal cranks. The larger sprockets produce lower gear ratios. Using them requires less pedaling effort, but
takes you a shorter distance with each pedal crank revolution. Moving the chain from a smaller sprocket of the gear cluster to
a larger sprocket results in a downshift. Moving the chain from a larger sprocket to a smaller sprocket results in an upshift. In
order for the derailleur to disengage the chain from one sprocket and move it on to another, the chain must be moving forward
(i.e. the rider must be pedaling forward).
2) Shifting the Front Derailleur:
The front derailleur, which is controlled by the left shifter, shifts the chain between the larger and smaller chainrings. Shifting
the chain onto a smaller chainring makes pedaling easier (a downshift). Shifting to a larger chainring makes pedaling harder
(an upshift).
b) Which gear should I be in?
The combination of largest rear, smallest front gears is for the steepest hills. The smallest rear, largest front
combination is for the greatest speed. It is not necessary to shift gears in sequence. Instead, find the “start-
ing gear” which is right for your level of ability -- a gear which is hard enough for quick acceleration but easy
enough to let you start from a stop without wobbling — and experiment with upshifting and downshifting to
get a feel for the different gear combinations. At first, practice shifting where there are no obstacles, hazards
or other traffic, until you’ve built up your confidence. Once you’ve learned the basics, experience will teach
you which gear is appropriate for which condition, and practice will help you shift smoothly and at precisely
the optimum moment.
3. Shifting an internal gear hub drivetrain
If your bicycle has an internal gear hub drivetrain, the gear changing mechanism will consist of:
• a 3, 5, 7 or possibly 12 speed internal gear hub
• one, or sometimes two, shifters
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