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D. Shifting Gears
Your multi-speed bicycle will have a derailleur drivetrain (see 1. below), an
internal gear hub drivetrain (see 2. below) or, in some special cases, a
combination of the two.
1. How a derailleur drivetrain works
If your bicycle has a derailleur drivetrain, the gear-changing mechanism will
have:
• A rear cassette or freewheel sprocket cluster
• A rear derailleur
• Usually a front derailleur
• One or two shifters
• One, two or three front sprockets called chainrings
• A drive chain
A. Shifting Gears
There are different types and styles of shifting controls: levers, twist grips, trig-
gers, combination shift/brake controls, push-buttons, and so on. Ask your dealer
to explain the type of shifting controls that are on your bike, and to show you
how they work.
The vocabulary of shifting can be pretty confusing. A downshift is a shift to a
“slower” gear, one which is easier to pedal. An upshift is a shift to a “faster”,
harder to pedal gear. What’s confusing is that what’s happening at the front
derailleur is the opposite of what’s happening at the rear derailleur (for details,
read the instructions on Shifting the Rear Derailleur and Shifting the Front
Derailleur below). For example, you can select a gear which will make pedaling
easier on a hill (make a downshift) in one of two ways: shift the chain down the
gear “steps” to a smaller gear at the front, or up the gear “steps” to a larger gear
at the rear. So, at the rear gear cluster, what is called a downshift looks like an
upshift. The way to keep things straight is to remember that shifting the chain in
towards the centerline of the bike is for accelerating and climbing and is called
a downshift. Moving the chain out or away from the centerline of the bike is for
speed and is called an upshift.
Whether upshifting or downshifting, the bicycle derailleur system design
requires that the drive chain be moving forward and be under at least some ten-
sion. A derailleur will shift only if you are pedaling forward.
CAUTION: Never move the shifter while pedaling backward, nor pedal backwards after having
moved the shifter. This could jam the chain and cause serious damage to the bicycle.
B. 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 sprocket to another. 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
4. Tech
Summary of Contents for multi-speed bicycles
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