Quoted message said:
Isn't mileage to failure perhaps a more meaningful measure of a
wheel's durability than what the failure mode is?
I'd say it's pound-miles. But wheel durability is a relative thing
that depends on where you live.
Despite assertions, not everybody's wheels will eventually wear out
their sidewalls if ridden far enough-- that us largely a factor of
local weather and soil conditions. I've ridden lots of miles in two
places-- Austin and Seattle. Austin has limestone-based soil, and
gets almost all its rain in the form of Biblical thundershowers (which
purge the streets clean of practically everything). If you don't want
to ride in the rain, you can usually just wait it out. As a result,
rims here last long enough to die from something besides sidewall
wear. I have a front wheel with about 35,000 miles on it that still
has its hard anodizing almost entirely intact. Only riding in the mud
causes folks here to have much sidewall wear.
In Seattle, the soil is granitic, and the rain comes in the form of an
eight-month-long session of drizzle (though the total annual
precipitation is about the same as Austin's). Everything gets coated
with a film of filth, not washed clean. You have to ride in it, if
you want to ride outside the summer months. So folks who do ride a
lot of miles inevitably wear out their rims if they use rim brakes.
(They also trash their axle bearings early and often.) I didn't
personally lose any rims to abrasion, but I use heavy rims-- and I
spread out my miles among approximately 20 bikes, some of them hub-
braked, during the almost six years I lived there.
Susceptibility to spoke bed cracking will be a bigger concern to folks
in a place like Austin than those in a place like Seattle, simply
because it's more likely to be the thing that takes their wheels out
of service in an expensive way.
Chalo