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6.7. Tires and Tubes
6.7.1.Tires
Bicycle tires are available in many
designs and specifications, ranging from
general purpose designs to tires
designed to perform best under very
specific weather or terrain conditions.
Your bicycle has been equipped with
tires that the bike's manufacturer
believed were the best balance of
performance and value for the use for
which the bike was intended. If, once
you've gained experience with your new
bike, you feel that a different tire might better suit your riding needs,
your dealer can help you select the most appropriate design. The
size, pressure rating, and on some high-performance tires the
specific recommended use, are marked on the sidewall of the tire
(see Fig. 20). The part of this information that is most important to
you is Tire Pressure.
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 way to inflate a bicycle tire to the correct pressure is with a
bicycle pump. Your dealer can help you select an appropriate pump.
CAUTION:
Gas station air hoses move a large volume of air very
rapidly, and will raise the pressure in your tire very rapidly. To avoid
overinflation when using a gas station air hose, put air into your tire
in short, spaced bursts.
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.
Inflating 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 and gas station air
hose pressure settings are generally inaccurate and should not be
depended on for consistent, accurate pressure. Instead, use a good
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 inflate your tires to
that pressure. Then, check inflation as described in Section 4.3 so
you'll know how correctly inflated tires should look and feel. 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
