A
bicycle is not just a mode of transport. Cycling
is a sport, a form of entertainment and an excellent
exercise. You must have ridden a bicycle yourself,
and probably know that it is a vehicle with two
wheels mounted, one behind the other, on a metal
frame. The rider supplies the power to move a
bicycle by pushing two pedals round in circle
with the feet.
When a rider pushes the pedals
of the bicycle they turn a toothed wheel called
the chainwheel. A chain fits around the edge of
the chainwheel and extends to a smaller toothed
wheel or sprocket on the rear wheel of the bicycle.
As the large sprocket or the chainwheel turns,
it moves the chain. The moving chain turns the
small sprocket and the rear wheel. All this sets
the bicycle moving. The rider used the handle
bars to steady and guide the bicycle and the brakes
to stop it.
NOTE: The largest trcycle
ever made hade side wheels which were 11 feet
in diameter, weighed over 2,000 lbs. and could
carry eight riders. |