Operation Manual

28
PART I
(continued from previous page...)
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
dierent speeds and on dierent surfaces. To better
understand this, experiment a little by walking your
bike and applying dierent 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 ying 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 eective 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 trac 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.
More info:
ROAD BIKES: DISC BRAKES
Now, go to PART II of this manual
and read “Understanding Disc Brakes
on Road Bikes”