Originally Posted by
BCRider
Assuming that it's an older wheelset it's possible that it largely sat unused but I'd think unlikely. So I'm shooting for undertensioned at some point that weakened a lot of the spokes. That and maybe something in the hub design that put a higher degree of loading on the head than normal.
Spokes with defects in manufacturing should/would show up their problems early and not after many years and I's assume more than a few miles of use.
But since we haven't heard about the wheel's history all this is just conjecture.
You raised another possbility when looking at the hub design...
For example, lacing a 7.0mm elbow spoke in today's standard alloy hub results in an angular lean and rest of the head in the hole when the wheel is finished and under tension. That of course results in a much higher load on one side of the flat saucer profile mushrooms common to el-cheapo spokes which doesn't occur as much in tight fitting and flush and well seated heads of 6.1mm/6.2mm elbows. That quick non-gradual transition point from mushroom to wire on the el-cheapo spoke looks pretty inviting as a failure point in such a situation.
=8-)
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