Only one more thing to add - at 235 to 240 pounds, a 24/28 spoke wheel
pair is probably too few. But, it is probably cheaper to rebuild and
stress relieve the wheels than to buy new ones, so I would try that
first. If you can remember, did you hear any pinging noises coming from
your wheels when the bike was brand new? That is a telltale sign of an
improperly stress-releived wheel, and indicates spokes seating and
unwinding, the result of which is a wheel that is at too low of tension.

Even experienced wheelbuilders fail to properly stress revieve spokes -
good advice from dianne..

dianne_1234 wrote:
On Sat, 29 May 2004 18:00:52 -0400, "Roger Zoul"
wrote:


This is my bike:
http://www.specialized.com/SBCBkMode...u ybug.j27008


Nice bike!


My bike has these wheels:
"Rolf design 700c twin spoke design high performance wheel set"


Only the paired spoke design is Rolf's, and that's really over a
century old. This design detail has nothing to do with your wheel
breaking spokes.


I weigh 235 to 240 lbs.


A little on the heavy side for a wheel with only 28 spokes, but still
not a cause for spokes to break.


The folks over
in .misc think that these spokes ought not to be popping


I agree.


and that I should have the wheel rebuilt


This shouldn't be necessary to stop spokes breaking if the spokes are
a reasonable fit in the hub holes. More below.


(I don't know what that means yet).


A rebuild is replacing the spokes, and the rim if it's damaged, and
re-tensioning the wheel.


The owner of the LBS told me today that she thinks I ride up hills in too
high a gear, and doing so puts a lot of stress on the rear wheel.


Clearly, she doesn't know why spokes break. You should be able to
pedal as hard as you like and not break any spokes by doing so.


Any comments/advice/suggestion would be greatly appreciated.


Unless there is some material flaw or dimensional anomaly in your
wheels, here's a sure fix to prevent broken spokes:

1. Measure the spoke elbow. If it's 6.5mm or less, the spokes are a
good fit in almost any hub's holes. If 7.0mm or more, have them
replaced.[1] Dimension E is what you're measuring, shown he
http://www.cnspoke.com/products/measure.htm

2. Replace any broken spokes.

3. Adjust hop, wobble, tension and dish. Aim for about 100 kg average
tension on the right side spokes. Lube nipples and spoke threads as
needed. The shop can easily do this.

** And here's the secret ingredient to preventing broken spokes: **
4. Stress relieve the wheel.[2] Basically, squeeze sets of four spokes
in your hands. Go around the wheel repeating until every spoke has
been momentarily over-tensioned like this.

Many shop mechanic wheel builders squeeze spokes like this, but few
squeeze hard enough or know that this relieves stress in the spokes
and prevents broken spokes. The harder the squeeze, the better the
resistance to spoke breakage.

How hard?
- Wear padded leather gloves. It'll hurt your bare hands otherwise.
- Squeeze hard to try and break any spokes that might be about to
break. Squeeze really hard. I dare you to break a spoke! :-)

5. Readjust hop, wobble, tension and dish as above.

[1] More details on elbow length he
http://www.peterwhitecycles.com/DTspokes.htm

[2] More details on stress relieving spokes he
http://yarchive.net/bike/stress_relieve.html