7
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 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.
