Re: Wheels for Heavy Rider

Tim McNamara

Tim Marshall <gunner.sabot@spam.ON.loaded.FIRE> writes:

> HI, this is my first post on rec.bicycles.*. I couldn't find
> anything on this in the faq at
> http://draco.acs.uci.edu/rbfaq/FAQ/index.html.
>
> I'm running through a stretch of bad luck with breaking spokes on my
> rear wheel

It's not bad luck, it's a wheel that wasn't built right or isn't
suited to you. If you weigh 500 lbs, it'll be hard to find a wheel
that will hold up, but if you weigh 300 lbs or less it shouldn't be
difficult at all. The key things are (1) enough spokes, (2) enough
spoke tension and (3) stress-relieving the spokes.

Enough spokes for a 26" wheel are 36 for almost everyone and 32 for
most. Enough tension is in part determined by the rim you are using,
but should be at least 100 kgf. The third is quite important, and the
book by Jobst Brandt mentioned by others contains the recipe for this
procedure; it may be in the FAQ as well.

Most original equipment wheels are undertensioned and have not been
stress relieved. A competent bike shop ought to be able to correct
both problems. Rust and corrosion from salt are not the cause of the
problem, contrary to your bike shop's claims, as the spokes are
stainless steel and not affected by salt. I ride year-round in
Minnesota, which has a liberal policy of salting roads (we start in
July to be ready for the first snowfall) and I have never had a spoke
fail from corrosion. In fact I can't remember the last spoke breaking
after I learned how to stress relieve years ago. I'll bet I haven't
had a broken spoke in at least 5 years, and those were on an 18" wheel
on a folding bike (Birdy with Sachs 3x7 hub). Other than that, it's
probably been almost 10 years since my last broken spoke. I weigh 215
lbs currently and 205-210 through most of the riding season (195 in
the days when I raced... sigh. I really should get disciplined and
get back to that weight. I felt good in those days).