Service - Diamondback MULTI-SPEED Owner's Manual

loose surfaces such as deep, dry sand.
Tire pressure that is too low for your weight and the riding
conditions can cause a puncture of the tube by allowing the
tire to deform suffi ciently to pinch the inner tube between the
rim and the riding surface.
!
CAUTION: Pencil type automotive tire gauges can be
inaccurate and should not be relied upon for consistent,
accurate pressure readings. Instead, use a high quality dial
gauge.
Ask your dealer to recommend the best tire pressure for
the kind of riding you will most often do, and have the dealer
infl ate your tires to that pressure. Then, check infl ation as
described in Section 1.C so you'll know how correctly infl ated
tires should look and feel when you don't have access to a
gauge. Some tires may need to be brought up to pressure
every week or two.
Some special high-performance tires have unidirectional
treads: their tread pattern is designed to work better in
one direction than in the 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.
2. Tire Valves
There are primarily two kinds of bicycle tube valves: The
Schraeder Valve and the Presta Valve. The bicycle pump you
use must have the fi tting appropriate to the valve stems on
your bicycle.
The Schraeder valve (fi g. 18) is like the valve on a car tire.
To infl ate a Schraeder valve tube, remove the valve cap and
clamp the pump fi tting 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
(fi g. 18) has a narrower
diameter and is only
found on bicycle tires. To
infl 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 infl ate. To infl ate a Presta valve with a Schraeder
pump fi 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 fi ts into the Schraeder
pump fi tting. Close the valve after infl ation. To let air out of
a Presta valve, open up the valve stem lock nut and depress
the valve stem.
!
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.

5. Service

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WARNING: Technological advances have made
bicycles and bicycle components more complex, and the
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