Quintana Roo bicycle Owner's Manual - page 24
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profile, the more likely it is that lighter components may be suitable for you.
Discuss your needs and your profile very honestly with your dealer.
Take these choices seriously and understand that you are responsible for
the changes.
A useful slogan to discuss with your dealer if you contemplate changing
components is “Strong, Light, Cheap –pick two.”
Original Equipment components
Bicycle and component manufacturers tests the fatigue life of the
components that are original equipment on your bike. This means that they
have met test criteria and have reasonable fatigue life. It does not mean
that the original components will last forever. They won’t.
if one was looking into a clear liquid. Delaminated areas will look opaque
and cloudy.
2. Bulging or deformed shape. If delamination occurs, the surface shape
may change. The surface may have a bump, a bulge, soft spot, or not be
smooth and fair.
3.A difference in sound when tapping the surface. If you gently tap the
surface of an undamaged composite you will hear a consistent sound,
usually a hard, sharp sound. If you then tap a delaminated area, you will
hear a different sound, usually duller, less sharp.
Unusual Noises:
Either a crack or delamination can cause creaking noises while riding.
Think about such a noise as a serious warning signal. A well maintained
bicycle will be very quiet and free of creaks and squeaks. Investigate and
find the source of any noise. It may not be a crack or delamination, but
whatever is causing the noise must be fixed before riding.
WARNING: Do not ride a bicycle or component with any
delamination or crack. Riding a delaminated or cracked frame,
fork or other component could lead to complete
failure, with risk of serious injury or death.
C. Understanding components
It is often necessary to remove and disassemble components in order to
properly and carefully inspect them. This is a job for a professional bicycle
mechanic with the special tools, skills and experience to inspect and
service today’s high-tech high-performance bicycles and their components.
Aftermarket “Super Light” components
Think carefully about your rider profile as outlined above. The more you
fit the “shorten product life” profile, the more you must question the use
of super light components. The more you fit the “lengthen product life”
be rough, sharp edges and maybe delamination of carbon fiber or carbon
fiber fabric layers. There will be no bending, buckling, or stretching.
If You Hit Something Or Have A Crash, What Can You Expect
From Your Carbon Fiber Bike?
Let’s say you hit a curb, ditch, rock, car, other cyclist or other object. At
any speed above a fast walk, your body will continue to move forward,
the momentum carrying you over the front of the bike. You cannot and
will not stay on the bike and what happens to the frame, fork and other
components is irrelevant to what happens to your body.
What should you expect from your carbon frame? It depends on many
complex factors. But we can tell you that if the impact is hard enough, the
fork or frame may be completely broken. Note the significant difference
in behavior between carbon and metal. See Section 2. A, Understanding
metals in this Appendix. Even if the carbon frame was twice as strong as
a metal frame, once the carbon frame is overloaded it will not bend, it will
break completely.
Inspection of Composite Frame, Fork, and Components
Cracks:
I
nspect for cracks, broken, or splintered areas. Any crack is serious. Do not
ride any bicycle or component that has a crack of any size.
Delamination:
Delamination is serious damage. Composites are made from layers of
fabric. Delamination means that the layers of fabric are no longer bonded
together. Do not ride any bicycle or component that has any delamination.
These are some delamination clues:
1. A cloudy or white area. This kind of area looks different from the ordinary
undamaged areas. Undamaged areas will look glassy, shiny, or “deep,” as
metals. Steel weighs 7.8 grams/cm3 (grams per cubic centimeter), titanium
4.5 grams/cm3, aluminum 2.75 grams/cm3. Contrast these numbers with
carbon fiber composite at 1.45 grams/cm3.
The composites with the best strength-to-weight ratios are made of carbon
fiber in a matrix of epoxy plastic. The epoxy matrix bonds the carbon
fibers together, transfers load to other fibers, and provides a smooth outer
surface. The carbon fibers are the “skeleton” that carries the load.
Why Are Composites Used?
Unlike metals, which have uniform properties in all directions (engineers
call this isotropic), carbon fibers can be placed in specific orientations to
optimize the structure for particular loads. The choice of where to place
the carbon fibers gives engineers a powerful tool to create strong, light
bicycles. Engineers may also orient fibers to suit other goals such as
comfort and vibration damping.
Carbon fiber composites are very corrosion resistant, much more so than
most metals.
Think about carbon fiber or fiberglass boats.
Carbon fiber materials have a very high strength-to-weight ratio.
What Are The Limits Of Composites?
Well designed “composite” or carbon fiber bicycles and components have
long fatigue lives, usually better than their metal equivalents.
While fatigue life is an advantage of carbon fiber, you must still regularly
inspect your carbon fiber frame, fork, or components.
Carbon fiber composites are not ductile. Once a carbon structure is
overloaded, it will not bend; it will break. At and near the break, there will