Electra Amsterdam Series, Руководство пользователя

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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 (fig. 16) is for the
steepest hills. The smallest rear and largest front combination is for the greatest
speed. 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 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. Learn to anticipate
the need to shift, and shift to a lower gear before the hill gets too steep. If you
have difficulties with shifting, the problem could be mechanical adjustment. See
your dealer for help.
WARNING: Never shift a derailleur onto the largest or the smallest
sprocket if the derailleur is not shifting smoothly. The derailleur may
be out of adjustment and the chain could jam, causing you to lose
control and fall.
e. What if it won’t shift gears?
If moving the shift control one click repeatedly fails to result in a smooth shift to
the next gear chances are that the mechanism is out of adjustment. Take the bike
to your dealer to have it adjusted.
2. How an internal gear hub drivetrain works
If your bicycle has an internal gear hub drivetrain, the gear changing
mechanism will consist of:
• a 3, 5, 7, 8, 12 speed or possibly an infinitely variable internal gear hub
• one, or sometimes two shifters
• one or two control cables
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 and push-buttons. 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: Never move the shifter while pedaling backward, nor
pedal backwards immediately 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