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G. Tires and Tubes
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. 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. 22). The
part of this information which is most important to you is tire pressure. The best and
safest way to inflate a bicycle tire to the correct pressure is with a bicycle pump which
has a built-in pressure gauge.
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.
fig.22
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.
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.