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a. A Brief Note About Shifting Gears
There are several different types and styles of shifting controls: levers, twist grips, triggers,
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 “lower” or
“slower” gear, one which is easier to pedal. An upshift is a shift to a “higher” or “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 tension. A derailleur will shift only
if you are pedaling forward.
CAUTION:
n
ever
move
the
shifter
while
pedaling
baCkward
,
nor
pedal
baCkwards
immediately
after
having
moved
the
shifter
. t
his
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 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 move the chain from one sprocket to
another, the rider must be pedaling forward.
c. 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).
d. Which Gear Should I Be In?
The combination of largest rear and smallest front gears is for the
steepest hills; the smallest rear and largest front combination is
for the greatest speed (fig. 16). It is not necessary to shift gears in
sequence. Instead, find the “starting 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
Fig.16
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