Diamondback Bicycle - Page 31

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WARNING: never Inflate a tIre Beyond the maxImum pressure marked on the tIre’s sIdewall. exceedIng
the recommended maxImum pressure may Blow the tIre off the rIm, whIch could cause damage to the BIke
and Injury to the rIder and Bystanders.
The best and safest way to inate a bicycle tire to the correct pressure is with a bicycle pump
which has an accurate built-in pressure gauge.
WARNING:
there Is a safety rIsk In usIng gas statIon aIr hoses or other aIr compressors. they are not
made for BIcycle tIres. they move a large volume of aIr very rapIdly, and wIll raIse the pressure In your
tIre very rapIdly, whIch could cause the tuBe to explode.
Tire pressure is given either as maximum pressure or as a
pressure range. How a tire performs under different terrain or
weather conditions depends largely on tire pressure. Inating
the tire to near its maximum recommended pressure gives the
lowest rolling resistance; but also produces the harshest ride.
High pressures work best on smooth, dry pavement.
Very low pressures, at the bottom of the recommended
pressure range, give the best performance on smooth, slick
terrain such as hard-packed clay, and on deep, 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 sufficiently 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 inate your tires to that pressure. Then, check ination as described in
Section 1.C.3. so you’ll know how correctly in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 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. 18a) 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. 18b) 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