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Adjusting
the Bike to Fit Your Body
Before you begin your ride, it is important that
the bike is adjusted to fit your body. Otherwise, the ride
will be uncomfortable and you will tire easily. Riding a
bike should be fun and the first place to start is with
a proper adjustment. Also note that when you are riding,
most of your weight is supported by your hands and seat,
with little taken up by your feet. Therefore, for the greatest
comfort, you need to make sure that the handlebars and seat
are adjusted so that your weight falls equally on each.
1. Seat Height: With the bike in an upright
position, straddle the top tube with both feet placed flat
on the ground. After first making sure that the seat is
level, adjust the height of the seat in such a way that
you can maintain a slight bend in your knee at the bottom
of the pedal stroke with your feet held level and the balls
of your feet placed over the pedal centers. Why this seat
height? It has been shown that the power of the pedal stroke
is the greatest when the leg is fully extended, and that
there is little power at the beginning of the stroke, when
the leg is folded. If your legs do not extend each
time you pedal then this can lead to leg cramping. This
happens because the muscle is not fully extended each time.
Cramping produces rapid fatigue and a burning sensation
caused by a build up of lactic acid in the blood. When people
ride with the seat too low, they can get cramped and never
develop any power or speed and give up cycling after a short
period. Why not just raise the seat to its proper position!
2. The next step is to set the horizontal
position of the seat. Mount the bike and with your feet,
rotate the crank backward until your right crankarm is pointing
straight ahead parallel to the ground. In this position,
a vertical line passing through the pedal axle should intersect
your knee about ½ inch behind the front of the knee.
To adjust, loosen the seat clamp and slide the seat either
forward of backward to get as close as possible to this
ideal position.
3. After the seat is adjusted, a rule for
adjusting the stem and handlebars, called the 1 inch rule,
applies fairly closely for general riding. This rule states
that the handlebars should be about 1 inch lower than the
seat height.This may vary with specialized riding needs.
For example, if you are riding on the road and desire a
more aerodynamic position, you may wish to drop the handlebars
to a height lower than the 1 inch. Since it is relatively
easy to adjust the handlebars, try experimenting with different
positions until you find one that suits your riding style.
4. Another way to adjust both the handlebars
and stem is to sit on the seat and lock your arms straight
in front of you and place your hands in position on top
of the brake levers. In this position, your back and the
bike’s top tube should form an angle that is equal
to or slightly smaller than 45 degrees. To adjust the bike
you will need to raise or lower the stem. Once the stem
is adjusted properly, when you ride the angle formed by
your body and your arms held straight in front of you and
your hands resting on the brake levers should not be greater
than 100 degrees or less than 90 degrees. Note: if it is
impossible to adjust the particular stem on your bike to
achieve this riding angle, then you should consider purchasing
a different stem. Note that this positioning of both the
stem and handlebars is again subject to changes, depending
on the type of bike you are riding and the riding position
(upright, prone, etc.) you prefer.
Seat
Adjustments
Careful adjustment of the seat can make all the difference
in riding comfort. It is critical to provide an overall proper
fit between the rider and the bike. When you are choosing
a bike size, you should be able to straddle the top tube and
have adequate clearance (most experts say around 2 inches)
when both your feet are on the ground. Make sure you are wearing
the shoes you will be using when you ride. The next thing
to do is to adjust the seat position, both up and down and
forward and backward. On a standard bike, the height of the
seat is determined by how deep the seatpost is set into the
seat tube on the bike. The tilt and left and right positioning
of the seat are controlled by the clamp that holds the seat
on the seat post. To adjust the seat to the proper height,
set the height such that when a pedal reaches its lowest point,
your knee is slightly bent. For the fore and aft setting,
sit on the seat and pedal backwards until the cranks are horizontal.
Then with the ball of your foot placed over the center of
the pedal, a vertical line passing through the ball of your
foot should intersect your knee just in back of your kneecap.
To adjust the seat to this position, loosen the seat clamp
and slide the seat to the correct position. If adjustment
doesn’t work, then the seat on your bike is probably
a poor fit to your anatomy! Try a new seat.
Handlebar
Stem Adjustments
The proper height of the stem and handlebar cannot be determined
until the seat is adjusted to its proper height and angle.
Once the seat is adjusted, you first check the height of the
handlebar in relation to the seat. For general purpose riding,
the handlebar should be about 1 inch lower than the seat.
Remember that the rule may vary somewhat for specialized riding
needs. If you want to ride with your back in an upright position,
then you would set the handlebar height the same as the seat.
If you wish to do a lot of fast riding in a low, aerodynamic
position, then you would set the handlebars a couple of inches
below the seat. The 1 inch rule should be considered a starting
point from which to find the height that suits your needs.
After the stem height has been set, you can then adjust the
handlebar position. To do this you first loosen the nut or
nuts on the stem that tighten the position of the handlebars.
Then adjust the position until your wrists are in the most
natural and comfortable position when you are sitting on the
seat and your hands are resting on top of the housing for
the brakes. Since the handlebars are so easily adjusted, try
experimenting with them until you get the best position for
your riding style.
It should be noted that for the Efun folding bicycles,
some of the models are equipped with handlebars, which can
be easily raised and lowered by simply using a quick release
that allows the handlebars and stem to slide up and down
within the head tube. Some models do not have the quick
release, but the height can be adjusted much like a regular
bike. On these models, the stem, headset and head tube is
below the folding mechanism. On some of the models the slope
of the handlebars can not be adjusted, as they are welded
to the stem as one piece.
Braking
Braking is one of the most important skills needed in bicycling.
And yes, braking is a skill that must be learned and practiced
in order to work effectively. Braking should be practiced
at slow speeds so that the rider feels comfortable and confident
is performing it in times of need. The number one braking
mistake is trying to stop with only the front brake. It is
dangerous because the body is still moving forward with great
speed and a quick stop will throw the rider over the handlebars.
Safety needs to be the first priority when bicycling. Just
as the front brake should not solely be used to stop a bicycle,
nor should just the rear brake. This is also dangerous, but
in a different way. Braking in the rear will cause the tire
to lock up and throw the bike into a skid. The rider may lose
control and fall off the bike. Proper braking involves using
both the front and rear brakes at the same time and with the
same pressure. In the case of needing to stop suddenly, the
rider must use the front and rear brakes as just mentioned
and lean back in the saddle at the same time. The sudden stop
stops the bike, but the rider will keep going unless action
is taken to keep the body from flying.
Braking while riding downhill is done as mentioned above
with a few more rules. The first instinct to slow the bike
down is to hold the brakes down slightly until the bottom
of the hill. This method does slow the bike down, but it
also harms the bike. The continuous braking causes a great
amount of friction and therefore heat is generated between
the rims and the brake pads. The brakes could possible be
damaged along with the tire and brake pads. The proper way
to decelerate is to use the front and rear brakes together
and firmly apply pressure every few seconds. This technique
cuts down on the amount of friction, which in turn is less
damaging to the bicycle. It helps to sit upright while on
the hill because it creates more air resistance to slow
down.
Braking in a curve involves yet another technique. One
should apply both brakes before the curve to slow down quickly
and then apply only the rear brake during the actual curve
if necessary. Remember not to apply too much pressure to
the rear brake because you are already on a curve and skidding
and falling would not be too much fun.
Changing
Gears
Gears, if used properly, help you to pedal with a minimum
of effort, thus allowing you to go farther with more endurance.
Bikes come with a variety of gearing and usually have from
3 to 18 gears. There are of course bikes with higher numbers
of gears than 18. The three-speed bikes have the gears housed
in the hub of the rear wheel. Bikes with a higher number of
gears have what is called derailleurs that move the chain
to a different sprocket (called a cog in the rear and a chainring
in the front) each time you shift gears. The number of gears
is found by multiplying the number of chainrings times the
number of cogs. For example, a “seven-speed bike”
has seven gears and has one chainring and seven cogs. A 21
speed bike usually has 3 chainrings and 7 cogs. The rear derailleur
(which moves the chain to different cogs) is the most instrumental
bike component in making the ride easy. It is used more often
than any other component you control while riding. The derailleur
not only moves the chain from cog to cog (or chainring to
chainring), but it also keeps the tension on the chain at
the correct level as the amount of chain wrap on the cassette
cog changes. Thus, you have a smooth changing of gears.
To change gears on a bike with a derailleur, continue to
pedal (maybe with slightly less pressure) and move the gear
shifter. The chain will “shift” to another cog
and thus the bike will be in a different gear. The smaller
cogs are on the outside of the hub and thus when you shift
to one of these small cogs from a larger cog, the pedaling
will tend to be harder, and you are in a higher gear. In
this higher gear (smaller cog), you will be able to attain
higher speeds as the rear wheel will be turning more revolutions
per front chainring revolution. In the lower gears (larger
cogs) you will have more power for going up hills.
You should change to a larger cog (lower gear) to get more
power when you see an approaching hill. Try to shift at
the bottom of the hill before you begin to climb. Also,
when going down a hill, change to a higher gear (smaller
cog) as you coast to the bottom and are about to begin pedaling
again.
Correct
Foot Positioning On the Pedals
The correct foot position is when the ball of the foot is
over the axle of the pedal. This positioning allows the natural
thrust of the foot to push us forward. A beneficial accessory
for the bike is a toe clip or a clip-on pedal. This accessory
ensures that the feet are properly on the pedals. They also
increase power, as no energy is lost keeping the feet in contact
with the pedal surface. Be sure to adjust the clips so that
the balls of the feet are over the axle of the pedal.
Safety
at High Speeds
Are bikes safe at high speeds? This, of course, depends on
many factors such as the condition of the bike, the experience
of the rider and the environment in which you are riding.
If the brakes are not working properly, the spokes are loose
or the frame is out of alignment, then you should not ride
at high speeds. In fact, you should not ride at all until
the bike is put back in to condition. You should evaluate
your bike and your experience before you attempt to ride too
fast. Safety is the absolute first consideration.
You must remember that when you are riding at high speeds
that there are real dangers involved. You should watch farther
ahead and anticipate dangers that could develop. You need
to realize that road hazards come upon you much quicker
and it takes much longer to come to a stop. There will be
an increased danger from motor vehicles and in making tight
turns, particularly when the riding surface is wet. Braking
distances increase rapidly with speed and the brakes on
a bike are not as good as those on a car. So if you are
following a car, stay a safe distance behind it and increase
that distance as your speed increases. When you are going
downhill at a high speed, you can lose control if you hit
a hole, a patch of ice, gravel, or a slick section of road.
Be very careful.
The
Wind and Aerodynamics
Everyone knows that riding against the wind makes bicycling
difficult. More work is required to ride through the wind.
The concept of aerodynamics that road bikers and racers know
very well can be applied here. The rider’s body is a
key contributor to air resistance. Racers have drop handlebars,
which force the upper body nearer to the handlebars and they
lower their head to be as parallel to the ground as possible.
Standard bikes do not have drop handlebars, but the rider
should replicate this position as much as possible and it
will make riding into the wind much easier.
Riding with the wind requires less energy, but takes more
time to stop. The wind may force you to ride faster than
desired and throw you around. Try to slow down to maintain
control.
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