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inoperative. Ask your dealer to make
sure that you understand the way the
brake quick release works on your bike
(see figs. 11. 12, 13. 14 & 15) and check
each time to make sure both brakes
work correctly before you get on the
bike.
2. How Brakes Work
The braking action of a bicycle is
a function of the friction between the
brake surfaces — usually the brake
pads and the wheel rim. To make
sure that you have maximum friction
available, keep your wheel rims and
brake pads clean and free of dirt,
lubricants, waxes or polishes.
Brakes are designed to control
your speed, not just to stop the bike.
Maximum braking force for each
wheel occurs at the point just before
the wheel “locks up” (stops rotating)
and starts to skid. Once the tire skids,
you actually lose most of your stopping
force and all directional control. You
need to practice slowing and stopping
smoothly without locking up a wheel.
The technique is called progressive
brake modulation. Instead of jerking
the brake lever to the position where
you think you’ll generate appropriate
braking force, squeeze the lever,
progressively increasing the braking
force. If you feel the wheel begin to lock up, release
pressure just a little to keep the wheel rotating just short of
lockup. It’s important to develop a feel for the amount of
brake lever pressure required for each wheel at different
speeds and on different surfaces. To better understand
this, experiment a little by walking your bike and applying
different amounts of pressure to each brake lever, until
the wheel locks.
When you apply one or both brakes, the bike
begins to slow, but your body wants to continue at
the speed at which it was going. This causes a transfer
of weight to the front wheel (or, under heavy braking,
around the front wheel hub, which could send you
flying over the handlebars).
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 traffic or other hazards
and distractions.
Everything changes when you ride on loose surfaces
or in wet weather. Tire adhesion is reduced, so the wheels