Page 38 - DK Children's Encyclopedia

Bicycles SEE ALSO

▸ ▸ Inventions
pp.136–137

A bicycle is a two-wheeled vehicle. There are many types ▸ ▸ Metals p.162
of bicycles. Some are for cycling on the road, others for ▸ ▸ Sports p.239
riding up and down mountains, and others for racing ▸ ▸ Games

around a track. Cyclists wear helmets to pp.240–241
protect their heads. ▸ ▸ Transportation
pp.258—259

How a bicycle works
To move a bicycle forward, a The hard outer covering
cyclist pushes down on the pedals. and spongy inner material
of bicycle helmets protect
These move a chain connected to riders’ heads if they fall.
the rear wheel. The bike is steered
with a set of handlebars, which
have brake levers to help the The right lever applies
rider to slow down. the front brake, and the
left lever applies the
rear brake.

This racing bike has The curved
very thin tires for handlebars on this
extra speed. bike allow the rider
to crouch down for
an easier ride.

The derailleur
is a part of the
bike that moves
the chain to a
different cog
for going up
or down hills.

Cycle racing
Bicycle wheels In the fastest type of bike
Most bicycle wheels have racing, riders compete on
traditional spokes (wire bicycles without brakes
or gears. They ride on
rods) that join the hub at sloped tracks in arenas
the center of the wheel called velodromes. Other
to the rim at the edge. types of races take place
on mountain tracks and
Racing wheels have just on roads. The most famous
a few large spokes. of these races is the
2,175 mile (3,500 km)
Traditional Tour de France.
spoked Carbon-fiber
wheel racing wheel
36

US_036_Bicycles.indd 36 16/05/2017 09:46