This article is from the Bicycles FAQ, by Mike Iglesias with numerous contributions by others.
From: Roger Marquis <firstname.lastname@example.org>
[More up to date copies of Roger's articles can be found at
Descending ability, like any other fine-motor skill, is best improved
with practice. The more time spent on technical descents the more
your confidence and speed will develop. The difficulty for bicyclists
is that each descent requires a climb. There are hot shots who
practice on their motorcycles before races with strategic descents.
For most of us the best solution is frequent group rides. Group
rides are the best path to developing real bike handling skills,
on descents and elsewhere.
After experience the second most important component of a fast
descent is relaxation. Too much anxiety can impair concentration
and cause you to miss important aspects of the road surface. Pushing
the speed to the point of fear will not help develop descending
skills. Work first on relaxation and smoothness (no sudden movements,
braking or turning) and speed will follow.
Third in importance is technique. Technique, however, is difficult
or impossible to learn from reading about it. For that reason this
article touches on just four of the many technical facets of
descending: apexing, breaking, lean, and passing.
Apexing is the art of straightening out a corner by using the
breadth of the lane or roadway. A fast descender will set up his
or her line well in advance of a corner, entering it from the
outside edge of the road for the widest possible angle. The apex,
or mid-point, is crossed at the opposite or inside edge of the
road, finally exiting again on the outside (always leaving room
for traffic, error and unforeseen hazard). The key is to _gradually_
get into position and _smoothly_ follow the line through the corner.
If you find yourself making _any_ quick, jerky movements take that
as a sign that you need to slow down and devote a little more
attention further up the road.
Use the brakes ONLY up to the beginning of a corner. NEVER APPLY
THE BRAKES THROUGH A CORNER. At that point any traction used for
braking will reduce the traction available for cornering. If you
do have to brake after entering a curve make every effort to
straighten your line before applying the brakes. If the road surface
is good use primarily the front brake. If traction is poor switch
to the rear brake and begin breaking earlier. In auto racing circles
there are two schools of thought on braking technique. One advocates
gradually releasing the brakes upon entering the corner. The other
advises hard braking right up to the beginning of the curve and
abruptly releasing them just before entering the curve. Cyclists
should probably combine these techniques depending on the road
surface, rim trueness, brake pad hardness, headset wear and the
proximity of other riders.
Motorcyclists and bicyclists lean their bikes very differently in
a corner. Motorcyclists keep their bikes as upright as possible
to avoid scraping the pegs or pipes. Bicyclists on the other hand
lean their bikes into the corner and keep the body upright. Both
motorcyclists and bicyclists extend the inside knee down to lower
the center of gravity. To _pedal_ through a corner make like a
motorcyclist and keep the bike upright while the inside pedal is
One of the most difficult aspects of fast descents is passing.
Unfortunately, there are good climbers who are slow descenders. As
a result it is not always possible to begin a descent ahead of
someone who you may want to pass. If you find yourself behind a
slow rider either hang out a safe distance behind or pass quickly
but carefully. Passing on a descent is always difficult and can be
dangerous. By the same token, if you find yourself ahead of someone
who obviously wants to pass, let them by at the earliest safe
moment. It's never appropriate to impede someone's progress on a
training ride whether they are on a bicycle or in a car. Always
make plenty of room for anyone trying to pass no matter what the
speed limit is.
Keep in mind that downhill racing is not what bicycle racing is
all about. There is no need to keep up with the Jones'. This is
what causes many a crash. Compete against yourself on the descents.
Belgians are notoriously slow descenders due to the consistently
rainy conditions there yet some of the best cyclists in the world
train on those rainy roads. Don't get caught pushing it on some
wet or unfamiliar descent. Be prepared for a car or a patch of dirt
or oil in the middle of your path around _every_ blind corner no
matter how many times you've been on a particular road. Take it
easy, relax, exercise your powers of concentration and hammer again
when you can turn the pedals.
If you're interested in exploring this further the best books (and
videos) on bike handling I've read are the "Twist of The Wrist"
series by motorcycle racer Keith Code (http://www.superbikeschool.com).
Roger Marquis (email@example.com)