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A wheel with more weight on it will accept greater brake pressure before
lockup; a wheel with less weight will lock up with less brake pressure. So,
as you apply brakes and your weight is transferred forward, you need to
shift your body toward the rear of the bike, to transfer weight back on to the
rear wheel; and at the same time, you need to both decrease rear braking
and increase front braking force. This is even more important on descents,
because descents shift weight forward.
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.
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 to begin with.
D. Shifting gears
Your multi-speed bicycle will have a derailleur drivetrain (see 2. below),
an internal gear hub drivetrain (see 3. 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,
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