GT Grade - Page 138

138
PART 2
Other Suspension Forks
138692 Rev 0 (04/22)
Section D. Inspect For Safety
GT Bicycle Owner’s Manual
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,
GT still urges you to 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 may be 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, fallen
cyclist or other object. First, read the Important
warnings at the beginning of PART II Section A.
Bicycles Cannot Protect You in this manual.
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 and fork is irrelevant to
what happens to your body.
What should you expect from your carbon
frame? It depends on many complex factors,
which is why we tell you that crash worthiness
cannot be a design criteria. With that important
note, we can tell you that if the impact is hard
enough, the fork or frame may be completely
broken. See Figure A on page 68. Note the
significant difference in behavior between carbon
and metal. 1. Understanding Metals in this
section. 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.
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 may be delamination
of carbon fiber or carbon fiber fabric layers.
There will be no bending, buckling, or stretching.
Our carbon frames/fork/components are
designed for normal riding loads with a factor of
safety. These frames/fork/components will be
broken by some crash or impact loads.
See “Composite Frame, Fork, And Component
Inspection” on next page.