jim beam wrote:
Ron Ruff wrote:

If I calculated correctly their "fatigue test" results seem a little
odd. 1,000,000 wheel revolutions is only 1,340 miles
(27*pi/12/5280*1,000,000). Even the CX-rays with 3,500,000 revolutions
only get 4,690 miles.

I would be nice to know more about that testing...

all i've discovered is that it was done by cycling from 90kgf to zero.
that's much higher than most wheels see in service. being as fatigue
life is usually regarded as having a logarithmic relation to stress, you
can see that your mileage will quickly increase with decreasing stress
cycle.

So, they stressed the spokes in an unusual way to get them to break
sooner... fairly standard, I guess. Still, it seems odd that they would
have presented it as "wheel revolutions" when it really isn't... and it
makes their spokes look bad.

Also, that 200lb cycle is roughly only 20% of the tensile strength that
they list elsewhere... a huge difference between fatigue and static
strength.

Do you know of any other (hopefully better) online data regarding spoke
fatique and strength?