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other. The sidewall marking of a unidirectional tire will have an arrow
showing the correct rotation direction. If your bike has unidirectional
tires, be sure that they are mounted to rotate in the correct direction.
6.7.2.Tire Valves
The tire valve allows air to enter the tire’s inner tube under pressure,
but doesn't let it back out unless you want it to.
There are primarily two kinds of bicycle tube valves (actually, there
are other designs, but they are seldom seen in the US any more):
The Schraeder Valve and the Presta Valve. The bicycle pump you
use must have the fitting appropriate to the valve stems on your
bicycle.
6.7.2.a. The Schraeder
Valve
(Fig. 21a) is like the valve on a car tire.
To inflate a Schraeder valve tube,
remove the valve cap and push the air
hose or pump fitting onto the end of the
valve stem. To let air out of a
Schraeder valve, depress the pin in the
end of the valve stem with the end of a
key or other appropriate object.
6.7.2.b. The Presta valve
(Fig. 21b) has a narrower diameter and
is only found on bicycle tires. To inflate
a Presta valve tube using a Presta
headed bicycle pump, remove the valve cap; unscrew
(counterclockwise) the valve stem lock nut; and push down on the
valve stem to free the valve. Then push the pump head on to the
valve and inflate. To inflate a Presta valve with a gas station air hose,
you'll need a Presta adapter (available at your bike shop) which
screws onto the valve stem once you've freed up the valve. The
adapter fits the end of the air hose fitting. To let air out of a Presta
valve, open up the valve stem lock nut and depress the valve stem.
6.7.2.c. Gluing Tubular Tires.
Tubular Tires are intended for racing only and must be installed by
an experienced mechanic. Please consult your Bicycle Dealer for
installation of tubular tires or instruction in how to do this.
6.7.3. Bicycle Suspension
Some Mountain Bikes come equipped with suspension systems that
are designed to smooth out some of the shocks encountered in off-
road riding. There are many different types of suspension systems -
too many to deal with individually in this Manual. If your bicycle has a
suspension system of any kind, ask your dealer to provide you with
the appropriate manufacturers’ adjustment and maintenance
instructions.
WARNING:
Failure to check and properly adjust the suspension
system may result in suspension malfunction, which may cause you
to lose control and fall.
CAUTION:
Changing suspension adjustment can change the
handling and braking characteristics of your bicycle. Never change
suspension adjustment unless you are thoroughly familiar with the
suspension system manufacturer's instructions and
