26
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 (fig. 14) 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.
!
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 or possibly 12 speed internal gear hub
• one, or sometimes two shifters
• one or two control cables
• one front sprocket called a chainring
• a drive chain
a. Shifting internal gear hub gears
Shifting with an internal gear hub drivetrain is simply a matter of moving the shifter to the indicated
position for the desired gear. After you have moved the shifter to the gear position of your choice, ease
the pressure on the pedals for an instant to allow the hub to complete the shift.
!
Fig.14
Содержание - V8.0
Страница 1: ...VERSION 8 0...
