(Carl Fogel) wrote in message . com...
Dear Rik,
I think that the original question was whether
these carbon Columbus Muscle Forks "break easily,"
not whether carbon forks in general last a long
time as long as you don't break them in a crash.
That is, what happens if you pop a pair of these
Columbus Muscle Forks in a vise and whack 'em with
a hammer to simulate a crash or wiggle 'em to mimic
ordinary riding stresses? Do the Columbus forks
bust more easily than other brands of carbon forks
or any kind of metal forks?
Like Dave, I appreciate your feedback, which suggests
that carbon forks in general survive ordinary riding
(but don't crash). That may be what Dave wanted to
know, but he might have been wondering if these Columbus
Muscles forks are the Ford Pinto of the carbon fork world,
too thin, too fragile, or somehow badly designed.
Carl Fogel
The following is from http://www.framebuilding.com/carbon%20forks.htm
although I dont specifically know how it compares to the testing
performed on carbon forks from other manufactures. ASTM standards call
for a load of 170 lbs. applied perpendicular to the steering axis,
both pushing and pulling for 50,000 cycles without failure. The
information below seems to suggest that the Columbus forks exceed
this.
-----------0---------
Columbus carbon forks are produced in accordance with ISO 9000. All
forks are marked and their history can be traced. The tests include
destruction testing and are performed on finished product samples.
They are very seve
* Frontal and side strength test:
A load of 200 N is first applied to the frontal part and then to
the side part of the fork. The flex is measured on each occasion and
this must not exceed a set value.
* Shock Test:
A mass of 250 N is dropped from a height of 430mm on a properly
restrained fork. In order to pass the test the fork must resist
without breakage or residual deformation.
* Static Test:
A load of 200 N is applied to the frontal part for 1 minute. In
order to pass the test the fork must resist without breakage or
deformation.
* Fatigue Test:
During this test an alternate force of +-600 N is applied. In
order to pass this test the fork must resist for 150,000 cycles
without breaking.