Spoke Breakage

Accidently, a spoke broke in its nipple on my front wheel. That seemed
quit odd to me. Any suggestions of how that could come about? To make
matters worse, the nipple is totally stuck on the rim, just can't get
it loose. How should I tackle this one?
Cheers, Mario.

On 8 Mar 2005 05:31:37 -0800, [email hidden]

(Mario) said:

Accidently, a spoke broke in its nipple on my front wheel. That seemed
quit odd to me. Any suggestions of how that could come about? To make
matters worse, the nipple is totally stuck on the rim, just can't get
it loose. How should I tackle this one?
Cheers, Mario.

Dear Mario,

In tests for Wheelsmith at Stanford in the early 1980's, 8
of 76 stainless steel spokes, or about 10%, failed at the
nipple when they were cycled until they broke:

http://www.duke.edu/~hpgavin/papers/HPGavin-Wheel-Paper.pdf

Front spokes fail more rarely because they carry less of the
weight and because they're symmetrically dished.

Drive-side rear spokes seem to fail far more often than the
other three sets of spokes, partly because they bear more
weight than the front, partly because they're more highly
tensioned than the non-drive-side spokes, and partly because
they're more prone to damage when chains and derailleurs
thrash into them.

As for the stuck nipple with the broken-off spoke end, does
it turn but not come out? That is, can you put a spoke
wrench or pliers on it and rotate it, but not get it out?

If it won't rotate, you probably have some impressive
corrosion.

If it rotates but won't come out, possibly there's some
corrosion or gunk in the way?

Carl Fogel