Giant - V8.0, Manual

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Fig.16
Woods/Dunlop valve Presta valve Schraeder valve
2. Tire Valves
There are primarily three kinds of bicycle tube valves: The Schraeder Valve, the Presta Valve and the
Woods/Dunlop valve. The bicycle pump you use must have the fitting appropriate to the valve stems on
your bicycle.
The Schraeder valve (fig. 16) is like the valve on a car tire. To inflate a Schraeder valve tube, remove the
valve cap and clamp the 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.
The Presta valve (fig. 16) 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 it up. Then push the pump head on to the
valve head, and inflate. To inflate a Presta valve with a Schraeder pump fitting, you’ll need a Presta adapter
(available at your bike shop) which screws on to the valve stem once you’ve freed up the valve. The adapter
fits into the Schraeder pump fitting. Close the valve after inflation. To let air out of a Presta valve, open up
the valve stem lock nut and depress the valve stem.
There is a third type of valve, which has a bottom similar to a Schrader and necks down to about the size of
a Presta. This is a Woods valve, also known as a "Dunlop" valve.
You can pump them up with a Presta
pump.
WARNING: Patching a tube is an emergency repair. If you do not apply the patch correctly or
apply several patches, the tube can fail, resulting in possible tube failure, which could cause you to
loose control and fall. Replace a patched tube as soon as possible.