Operation Manual

37
2. Tire Valves
There are primarily two kinds of bicycle tube valves:
The Schrader Valve and the Presta Valve. The bicycle
pump you use must have the tting appropriate to the
valve stems on your bicycle.
The Schrader valve (g. 18) is like the valve on a car
tire. To inate a Schrader valve tube, remove the
valve cap and clamp the pump tting onto the end
of the valve stem. To let air out of a Schrader valve,
depress the pin in the end of the valve stem with the
end of a key or other appropriate object.
The Presta valve (g. 18) has a narrower diameter and
is only found on bicycle tires. To inate 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 inate. To inate a Presta valve with a Schrader
pump tting, 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 ts into the
Schrader pump tting. Close the valve after ination.
To let air out of a Presta valve, open up the valve stem
lock nut and depress the valve stem.
Figure 18.
WARNING
We highly recommend that you carry a spare
inner tube when you ride your bike.
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.
Schrader valve
Presta valve
Valve Stem
Locknut