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Two keys to effective speed control and safe stopping are controlling wheel
lockup and weight transfer. This weight transfer is even more pronounced if
your bike has a front suspension fork. Front suspension “dips” under braking,
increasing the weight transfer (see also Section 4.F). Practice braking and weight
transfer techniques where there is no trafc or other hazards and distractions.
Everything changes when you ride on loose surfaces or in wet weather. It will
take longer to stop on loose surfaces or in wet weather. Tire adhesion is reduced,
so the wheels have less cornering and braking traction and can lock up with less
brake force. Moisture or dirt on the brake pads reduces their ability to grip. The
way to maintain control on loose or wet surfaces is to go more slowly.
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.
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