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Bike Setup

                       
                                

Bike Setup

Always difficult to determine if your bike is the correct size for you by
riding it. If you hurt after riding, is it the bike or muscles fighting back?
Here is one method of determining proper bike dimensions. It came from one
of the trainers of the Postal Team after the 1999 Tour d' France

Road bikes:

Frame: Measure your inseam from crotch to floor with bare feet six inches
apart, then multiply by 0.67. This equals your road frame size, measured
along the seat tube from the center of the crank axle to the center of the
top tube. As a double check, this should produce 4 to 5 inches of exposed
seatpost when your saddle height is correct. When the crankarms are
horizontal, the top tube should be right between your knees when you squeeze
them together.

Handlebar: Bar width should equal shoulder width to open your chest for
better breathing. A bit too wide is better than too narrow. Make sure the
hooks are large enough for your hands. Modified "anatomic" curves may feel
more comfortable to your palms. Position the bottom, flat portion of the bar
horizontal or pointed slightly down toward the rear hub.

Brake Levers: Move them around the curve of the bar to give you the best
compromise between holding the hoods and braking when your hands are in the
hooks. Most riders do best if the lever tips touch a straightedge extended
forward from under the flat, bottom portion of the bar. The levers don't have
to be symmetrical - remember Andy Pruitt's rule. If your reach is more
comfortable with one lever closer than the other, put 'em that way.

Stem Height: Start with the top of the stem about one inch below the top of
the saddle. This should give you comfortable access to every hand position.
As time goes by, think about lowering the stem as much as another inch (not
all at once) to improve your aerodynamics. If your lower back or neck starts
complaining, or if you notice you've stopped using the drops, go back up.
Never put the stem so high that its maximum extension line shows, or it could
be snapped by your weight on the bar.

Top-tube and Stem Lengths: Combined, these two dimensions determine "reach."
Depending on your anatomy and flexibility, your reach could be longer for
better aerodynamics, or it may need to be shorter for back or neck comfort.
For most riders, when they're comfortably seated with their elbows slightly
bent and their hands on the lever hoods, the front hub will be obscured by
the handlebar.

Saddle Height: This is the biggie. You'll find various methods for
calculating this critical number. Here's the one I like best. It has become
known as the LeMond Method, because Greg brought it to us from his Renault
team in the '80s. (Invite a friend over so you can help each other and both
wind up with primo positions.) Stand on a hard surface with your shoes off
and your feet about six inches apart. Using a metric tape, measure from the
floor to your crotch, pressing with the same force a saddle does. Multiply
this number by 0.883. The result is your saddle height, measured from the
middle of the crank axle, along the seat tube, to the top of the saddle.

Add 2 or 3 mm if you have long feet in proportion to your height. If you
suffer from chondromalacia (knee pain caused by damage to the underside of
the kneecap), a slightly higher saddle may feel better. However, it should
never be so high that your hips must rock to help you reach the pedals. If
this formula results in a big change from the height you've been using, make
the adjustment by 2 or 3 mm per week, with several rides between, till you
reach the new position. Changing too fast could strain something.

Saddle Tilt: The saddle should be level, which you can check by laying a
yardstick along its length and comparing it to something horizontal like a
tabletop or windowsill. A slight downward tilt may be more comfortable, but
be careful. More than a degree or two could cause you to continually slide
forward, putting pressure on your arms and hands.

For/Aft Saddle Position: Sit comfortably in the center of the saddle, click
into the pedals, and set the crankarms horizontal. Hold a weighted string to
the front of your forward kneecap. For most of us, the string should touch
the end of the crankarm. This is known as the neutral position. Loosen the
seatpost clamp so you can slide the saddle to get it right. Seated climbers,
time trialists, and some road racers may like the line to fall a centimeter
or two behind the end of the crankarm to increase pedaling leverage. On the
other hand, track and criterium racers may like a more forward position that
breeds leg speed. Remember, if your reach to the handlebar is wrong, use stem
length to correct it, not fore/aft saddle position.

Feet: Some of us walk like pigeons, others like Charlie Chaplin. Your
footprints as you leave a swimming pool will tip you off. To make cycling
easier on your knees, shoes cleats must put your feet at their natural angle.
This is a snap with clipless pedal systems that allow feet to pivot freely
("float") several degrees before release. Then all you need to do is set the
cleats' fore/aft position, which is easy. Simply position them so the widest
part of each foot is centered on the pedal axle. If you experience discomfort
such as tingling, numbness or burning (especially on long rides), move the
cleats rearward as much as a centimeter.

Crankarm Length: In general, if your inseam is less than 29 inches, use
165-mm crankarms; 29-32 inches, 170 mm; 33-34 inches, 172.5; and more than 34
inches, 175 mm. Crankarm length is measured from the center of the fixing
bolt to the center of the pedal mounting hole. It's usually stamped on the
back of the arm. If you use longer crankarms than recommended, you'll gain
leverage for pushing big gears but lose some pedaling speed.

Mountain Bikes:

Frame: If you ride trails, sometimes you'll be getting off the bike in a
hurry when you least expect it. This makes it nice to have plenty of
clearance between your crotch and the top tube. You'll get it when your
mountain bike is about four inches smaller than your road bike. This isn't as
critical if you'll be riding only on pavement or smooth dirt roads, but
there's no advantage to having a frame any larger than the smallest size that
provides enough saddle height and reach to the handlebar. Smaller frames are
lighter, stiffer and more maneuverable. Because manufacturers specify frame
size in different ways, use the stand-over test. When straddling the bike
while wearing your riding shoes, there should be at least four inches between
your crotch and the top tube.

Saddle Height: Long seatposts (350 mm) are common, which is why frames can be
relatively small. However, the post should never be extended so far that the
maximum extension line shows or it could snap off. Like on a road bike, your
knee should remain slightly bent (20 to 25 degrees) at the bottom of the
pedal stroke. For a precise calibration, use the LeMond Method in the road
position guidelines. Sometimes, though, you'll want to put the saddle a bit
lower. On a descent this will help you keep your weight low and rearward for
better control. On rough ground it keeps you from being jackhammered by the
saddle.

Saddle Tilt: Because you're moving around a lot, a level seat isn't
essential. You might find that a slight nose-down tilt reduces crotch
pressure and stops your shorts from snagging when you sit down. Go easy or
you'll be sliding forward and putting extra pressure on your arms.

Fore/Aft Saddle Position:Use the same method given to roadies. Remember, you
slide your saddle to get the correct knee-over-pedal relationship, not to
change your reach to the handlebar. That's why stems come in different
lengths.

Stem: The length and height are important for weight distribution and bike
control. When you're climbing, for instance, you need enough weight on the
front wheel so it won't pop up and you can steer. The stem should put the bar
1-to-2 inches below the top of the saddle, and be long enough to give you
about a 45-degree forward lean with flexed elbows. If yours doesn't do this,
it's easy to find one that will. Stems come in a wide range of extensions and
rises. For the type with adjustable height, make sure it's inserted deep
enough to bury the maximum extension line.

Back: Your position is good when your back makes about a 45-degree angle
during normal riding. If you're more upright, you won't get as much pedaling
power from the gluteus muscles in your butt. The glutes are as important as
your quads for making the bike go. A forward lean also reduces the weight on
your saddle so impacts aren't as severe, and it helps the front wheel stay
grounded.

Hands and Wrists: Angle the brake levers so that your wrists are straight
when you're crouched over the saddle and braking, like you do on a downhill.
Set the levers close enough to the grips that you can squeeze them with a
finger or two and still hold the bar firmly. Avoid white knuckles. Keep your
thumbs under the bar (not resting on top) so your hands can't slip off.

Handlebar Width: A wide (long) bar improves slow-speed steering. A narrow
(short) bar gives a quicker response and fits better through tight
singletrack. You can trim a bar with a hacksaw or pipe cutter, but before you
do, move the controls inward and take a ride to see how the shorter width
feels. Then before you cut, leave a little extra if you want to install
bar-ends. In general, new bars come in widths of 22 to 25 inches. If your
present bar is more than a couple of years old and you've had a few crashes,
consider replacing it with a new bar of the desired length rather than
resizing it. A fatigued bar can snap at the stem.

Handlebar Sweep: Most bars have a slight bend of about 5 degrees. This adds
some arm and wrist comfort and has the effect of moving the bar a bit closer.
Keep this in mind if you change bars, because it may mean you'll need to
change stem length, too. A bar with an upward bend (rise) lets the stem be
lower or have less upward angle. A rise bar is typically wide for good
slow-speed handling.

Bar-ends: Install these short, forward extensions to get a longer lower
position on fast, open trails, and to have better leverage when climbing.
Choose a model that curves inward to protect you hands and reduce the chance
of hooking bushes or branches on narrow singletrack. Angle them upward a few
degrees. Bar-ends can be installed on most handlebars, but aren't recommended
on some ultralight models.

Crankarm Length: This should vary with the size of the rider, which is why
bike makers usually vary it with the size of the frame. In general, longer
cranks provide better leverage at the expense of pedaling speed. For trail
riding, leverage is what you want. Go for crankarms that are 2.5 or 5 mm
longer than your road bike size.

 

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