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Le Tour de France: The Great Race
Aerodynamics play a huge role in
the biggest cycle race in the world, the Tour de France. Covering
over 4,000 kilometers in three weeks of daily racing, "The
Tour" is an all-out test of riders' speed, strategy, and
heart. Cyclists travel mostly in a pack, called the "peloton," which
creates a huge draft. In each day's "stage," the
racers test themselves against each other and against the mountainous
terrain of the Alps and the Pyrenees. Stages can last for six
to eight hours, covering 90-150 miles (145-240 km), and racers
can burn over 10,000 calories a day. The winner is the rider
with the lowest total time for all stages. As 1988 Tour champion
Pedro Delgado put it, "This is the war of the cyclists.
That's what we call it."
Though the climbs in the Alps and
the Pyrenees are arduous, the vicious crosswinds that play
across the fields of France mean that the flats offer little
respite. A lone cyclist can be battered to a standstill. In
these conditions, the peloton strings out into a diagonal paceline
formation called an "echelon." Like a paceline, this
diagonal line of riders is designed to let the lead riders
fight the wind, while following riders are sheltered, awaiting
their turn at the front. When an echelon forms, its length
is limited by the width of the road, resulting in a fierce
battle in the "gutter" for the final places in the
echelon line. Since the riders in the echelon have a 15-30%
advantage in the wind, a failure to make the first echelon
can be the difference between a chance to win the stage and
a long futile chase.
In mountain biking, drafting seems to
be less important. U.S. cross-country champion Ruthie Matthes
explained, "In mountain biking, drafting doesn't tend to
be a factor. The speeds are slower (than road racing) and the
rolling resistance is greater. It helps to draft for the mental
aspect, for keeping pace with someone ahead of you. But as far
as using less energy, it's not really a big factor." Besides
the rolling resistance and slower speeds, the twisting up-and-down
nature of most mountain biking courses would make drafting extremely
difficult.
Recumbents
and HPVs
Drafting is not always an option and its benefits are somewhat limited. The
easiest way to overcome wind resistance and reduce drag is to become more streamlined.
In recumbent design, the cyclist pedals from a seated position, which gives
the cycle a lower profile and makes it aerodynamically more efficient. Recumbent
cycles have been around for over 100 years, although they have never enjoyed
the popularity of the upright safety cycle, which remains the design people
associate with cycles.
Human-powered vehicles became popular
during the the 1970s. During that decade the popularity of the
cycle reached a new high and two OPEC oil embargos increased
public awareness of alternative methods of transportation. Most
HPVs use a recumbent design and a lightweight outer shell to
make the vehicle more streamlined and to reduce skin friction.
HPVs can travel at very high speeds. The world record holder
in the 200 meters traveled at over 68 miles per hour (110 km).
A custom-made
recumbent cycle
Recumbents hold many speed and endurance
records and are quite comfortable to ride. Recumbents are so
efficient that many races do not allow recumbents to enter for
fear that the cyclists on the traditional safety design will
be at a disadvantage. There are a few disadvantages to the recumbent
design. One is the cost; recumbents are not mass-produced and
cost more than safety cycles. In addition, recumbents are harder
to see on the road - most use an orange safety flag so automobile
drivers can more easily avoid them.
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