GT Grade, Руководство пользователя

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PART 1
4.D - Shifting Gears
Section 4. Tech
GT Bicycle Owner’s Manual
2. Adjusting your coaster brake
Coaster brake service and adjustment requires
special tools and special knowledge. Do not
attempt to disassemble or service your coaster
brake. Take the bicycle to your dealer for coaster
brake service.
4.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 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.