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Old 05-29-18, 08:31 AM
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Originally Posted by Kontact View Post
Spokes fatigue from variations in spoke tension within their normal tension range. If the elbows aren't seated properly the fatigue load gets concentrated there and the elbows break. If there are too few spokes the tension they carry increases as does the amplitude of tension they see as the wheel rolls, wearing the spokes faster.

In a properly spec'd and built wheel, the spokes will never break from fatigue. The rim will fail first, followed by the aluminum flanges. Wheels that break spokes have something essential wrong with them in either design or execution, because steel spokes are much more fatigue resistant that the aluminum rim and hub.
Your two statements are at odds with one another. I agree that spokes fatigue from variations in spoke tension. Their fatigue life isn't infinite. I also agree that fewer spokes put more load on each spoke and result in increased fatigue.

The fact that we know about spoke fatigue, however, negates your second statement. "Never" is a long time. Spokes can certainly outlast rims but a worn out rim isn't the end of a wheel. It usually is because finding an identical rim or even a rim with an identical ERD usually isn't worth the hassle and expense. But the spokes will eventually start to fail with enough miles on them no matter how well built the wheel is.

I would also disagree that the hub flange goes before the spokes. Hub flange failure is rare even when the hub is reused multiple times in wheel building.
Stuart Black
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