Chapter. 10 Wheels/Tires, Pedals, Hubs & Bottom Bracket - MARIN Owner's Manual

C H A P T E R 1 0
W H E E L S / T I R E S , P E D A L S ,
H U B S & B OT TO M B R A C K E T
WHEELS/TIRES
(See Chapter 2 "Removing and Installing Front and Rear Wheels"
first.)
TIRE CARE:
Tire neglect is often the cause of the greatest headaches in bicycle
maintenance. It is normal for inner tubes to lose air over time. Tires
are subject to wear.
INFLATION:
Check tire inflation by pinching the tire between thumb and forefin-
ger. It should feel firm. The shape of the tire should change very little
as you get off your bicycle. Every now and then use a tire gauge to val-
idate your assessment of tire inflation.
Avoid using service station high pressure air hoses. They easily over-
fill bicycle tires and can cause serious damage to the inner tube. You
should use a bicycle pump when ever possible. Proper air pressure
ranges for any type of tire are listed on the side wall of the tire. If two
air pressures are listed, the higher is for on-road and lower is for off-
road riding.
A NOTE ON TIRE VALVES:
There are two types of valves used on the inner tubes on Marin bicy-
cle, one of which is similar to that found on automobiles called the
"Schraeder" or "American valve." The other type is known as the
"Presta" or "French valve." Presta valves are slender metal valves and
are most commonly used on bikes with narrow rims.
Learn what type of valves your bicycle
has. It will be the first question the bike
shop asks you when you go to buy an
extra tube. Most quality bicycle pumps
come equipped to fit either type of
valve. Read the instructions with your
pump so you can effectively use it on
either type of valve.
WHEEL INSPECTION:
Inspect the rims of your bicycle's wheels before every ride, especial-
ly checking for dents. A rim with major dents or any cracks must be
replaced. Also check for wheel "trueness": Spin each wheel and make
sure that it spins straight and true, without wobble. Periodically check
for any broken spokes. Have your Marin dealer re-adjust loose spokes
and replace broken ones.
Or course, you should periodically check your tires for weather
checking or any imbedded foreign objects such as thorns, pebbles,
glass or nails.
FLATS:
Flats can occur at any time. From the first mile you ride on your new
Marin bicycle, you are at risk of a flat. Flats are considered part of nor-
mal wear and tear and are not covered under warranty by Marin
Mountain Bikes or your dealer. Please be responsible for yourself and
carry appropriate materials to fix a flat and learn how to make this
simple repair yourself.
HOW TO FIX A FLAT:
After removing the wheel from the bicycle, remove one side of the
tire from the rim. You may be able to do this with your hands but, if
tools are required, use tire levers, do not use screwdrivers or other
sharp objects as these can further damage the inner tube. Pull the tire
completely off the rim, pulling the inner tube out completely but
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VALVES
SCHRADER
PRESTA