Schwinn Hybrid Owner's Manual page 67

Appendix A
WARNING!
Frequent inspection of your bike is important to your safety.
Follow the Mechanical Safety Check in Section 1.C of this Manual
before every ride.
Periodic, more detailed inspection of your bicycle is important.
How often this more detailed inspection is needed depends
upon you.
You, the rider/owner, have control and knowledge of how often
you use your bike, how hard you use it and where you use it.
Because your dealer cannot track your use, you must take
responsibility for periodically bringing your bike to your dealer
for inspection and service. Your dealer will help you decide what
frequency of inspection and service is appropriate for how and
where you use your bike.
For your safety, understanding and communication with your
dealer, we urge you to read this Appendix in its entirety. The
materials used to make your bike determine how and how
frequently to inspect.
Ignoring this WARNING can lead to frame, fork or other
component failure, which can result in serious injury or death.
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A. Understanding metals
Steel is the traditional material for building bicycle frames. It
has good characteristics, but in high performance bicycles,
steel has been largely replaced by aluminum and some
titanium. The main factor driving this change is interest in
lighter bicycles by cycling enthusiasts.
Properties of Metals
Please understand that there is no simple statement that
can be made that characterizes the use of different metals
for bicycles. What is true is how the metal chosen is
applied is much more important than the material alone.
One must look at the way the bike is designed, tested,
manufactured, supported along with the characteristics
of the metal rather than seeking a simplistic answer.
Metals vary widely in their resistance to corrosion. Steel
must be protected or rust will attack it. Aluminum and
Titanium quickly develop an oxide film that protects the
metal from further corrosion. Both are therefore quite
resistant to corrosion. Aluminum is not perfectly corrosion
resistant, and particular care must be used where it contacts
other metals and galvanic corrosion can occur.
Metals are comparatively ductile. Ductile means bending,
buckling and stretching before breaking. Generally speaking, of
the common bicycle frame building materials steel is the most
ductile, titanium less ductile, followed by aluminum.