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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 inflate your tires to that pressure. Then,
check inflation as described in Section 1.C so you’ll know how correctly inflated
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, so it is important to
check your tire pressures before every ride.
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 fitting
appropriate to the valve stems on your bicycle.
The Schraeder valve (fig. 18a) is like the valve on a car tire. To
inflate a Schraeder valve tube, remove the valve cap and clamp the
pump fitting 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 (fig. 18b) has a narrower diameter and is only found
on bicycle tires. To inflate 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 inflate. To inflate a Presta valve with a Schraeder
pump fitting, 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 fits
into the Schraeder pump fitting. Close the valve after inflation. To let air out of a
Presta valve, open up the valve stem lock nut and depress the valve stem.
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.
WARNING: Not all bicycles can be safely retrofitted with some types
of suspension systems. Before retrofitting a bicycle with any
suspension, check with the bicycle’s manufacturer to make sure that
what you want to do is compatible with the bicycle’s design. Failing to do
so can result in catastrophic frame failure.
Felt Equilink Suspension System: The Equilink Suspension System is a
proprietary suspension system that requires its own method of adjustment
unlike most other bicycles. To learn more please refer to the instruction
manual included in the box with your bicycle or visit: http://www.
feltbicycles.com.
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. 17). The part of this
information which 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 and safest way to inflate a bicycle tire to the correct pressure is with
a bicycle pump which has a 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. Inflating the tire to near its maximum recommended pressure