Owner`s manual

32
Cervélo Owner’s Manual
Factors that lengthen product life:
• Smooth, fluid riding style
• No “hits,” crashes, jumps, other “shots” to bike
• Low mileage
• Lower body weight
• Less aggressive rider
• Non-corrosive environment (dry, salt-free air)
• Clean riding environment
WARNING: Do not ride a bicycle or component with any crack,
bulge or dent, even a small one. Riding a cracked frame, fork or
component could lead to complete failure, with risk of serious
injury or death.
B. Understanding Composites
All riders must understand a fundamental reality of composites.
Composite materials constructed of carbon fibers are strong and light,
but when crashed or overloaded, carbon fibers do not bend, they break.
What Are Composites?
The term “composites” refers to the fact that a part or parts are made
up of different components or materials. You’ve heard the term “carbon
fiber bike.” This really means “composite bike.”
Carbon fiber composites are typically a strong, light fiber in a matrix
of plastic, molded to form a shape. Carbon composites are light relative
to metals. Steel weighs 7.8 grams/cm
3
(grams per cubic centimeter),
titanium 4.5 grams/cm
3
, aluminum 2.75 grams/cm
3
. Contrast these
numbers with carbon fiber composite at 1.45 grams/cm
3
.
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 be rough, sharp edges and maybe delamination of
carbon fiber or carbon fiber fabric layers. There will be no bending,
buckling, or stretching.