spoke breakage - next move?
I've got a Stan's Arch factory built rear wheel here that is shedding spokes like a meth addict sheds teeth. Once it started, it seems like every 3 or 4 rides, one breaks. Today is the first time I actually heard one snap. So far I've replaced 5, all non-drive side leading spokes, and all right in a row. I mark them so I know which ones they are.
Is this kind of failure typical once one breaks, the next one is overstressed, and the next one, wash rinse repeat?
If you were me, would you go ahead and replace the last 3 leading NDS spokes that haven't broken yet? I'm not sure if that will really buy me anything, but I'm willing to do it if it'll stop the breaking spokes and keep me from messing with it for a while. I'm also tempted to just respoke the whole wheel, but not sure that's really needed.
Thanks for any help
I may or may not be laughing at you.
I was recently given a pair of Stan's Iron Crosses to true. They were bought straight from Stan's built up with the house hubs and house build. Rode once and they were all over the place. The spoke tensions were all over the charts.
I completely loosened em up and retensioned them.
Now they're fine.
I would replace those spokes on yours and retension.
Stress relieving wheels (Jobst Brandt; Mike Prime)
From: email@example.com (Jobst Brandt)
Subject: Re: Question for Jobst
Date: 28 Jul 2000 00:23:29 GMT
cLaWs ??? (who dat?) writes:
>> To stress relieve, grasp most parallel pairs of spokes and squeeze
>> them together as though you were trying to break them by over
>> tensioning. This relaxes the high stress points by yielding them.
> How hard should I squeeze? Hard enough to make the rim move
> laterally in the stand? Only hard enough to make the spokes flex?
> Hard enough for my knuckles to turn white and my fingertips to
> nearly bleed?
Use some common sense. I do it with bare hands, one hand on each side
of the wheel, making a quick grasp. Unless you are unusually strong
and have more calloused hands than I, you won't damage the wheel. The
exception would be rims under 300g like Scheeren Weltmeisters that at
280g take a bit of care. The wheel should withstand the stretching
grip of an athletically inclined person. I can do one wheel, once
around before I feel my hands need a rest. I wouldn't do a whole lot
of wheels in succession without leather gloves to protect my hands.
> I have been doing the first one, watching the rim deflect about 2-3
> mm, and it seems to work; I am afraid I may be over doing it and
> shortening the rim or spoke life.
Not to worry, you won't shorten spoke life. You might bend the rim,
but only if the spokes are already too tight.
The way I discovered this was that I had a pair of wheels that forever
broke spokes, wheels that I subsequently seldom used. I had them
shipped to me on a bike tour after I had crashed both wheels on
Monitor Pass CA. After riding from Reno (NV) to Fort Bragg (CA) on
the Pacific Coast. I had two spoke failures. With a 5-speed Regina FW
but a large flange hub, I could get at the spokes by disassembling the
FW at a gas station, I could take off the rotor to expose the spokes
for removal. (There were no bicycle shops around in those days.)
I had plenty of spokes, as one did then, and began replacing them,
each time trying to break others that might already be cracked by
"stress relieving" although I was unaware of the effect at that time.
In all I replaced five spokes, as I recall, and reassembled my FW.
Afterward, I rode that wheel for a long time without further failures.
A couple of years later, in Florence (I) I saw a team mechanic finish
a wheel and lay it on the floor to walk on the spokes with his tennis
shoes. I asked what this awful looking routine did to which he
replied with a sly grin that it made wheels last a long time. It was
then that I put it together. You see, I had not noticed that my bad
wheels stopped breaking spokes after I had stretched them, they just
worked the way wheels should. Seeing Mara walk on wheels that he had
built for Gastone Nencini caught my attention.
I am dismayed that I cannot persuade Holland Mechanics to call their
"Stabilizer" what it really is, a stress reliever on their web site:
http://www.holland-mechanics.nl/ (under PRODUCTS, STABILIZER). This
machine presses spokes in pairs from opposite sides of the wheel
toward the central plane, thereby stretching and yielding their high
stress points to relax residual stress concentrations.
They remind me of my experience explaining to the former Wheelsmith
bicycle shop how important this process is and how it achieves its
effect, to which then they responded by calling it "seating the
spokes" or "pre-stressing". This became more obvious when Wheelsmith
reviewed my book for Bicycling Magazine, panning it as light weight,
Ive had 3 stans factory built wheels. One had spokes so crazy long that they could not be tensioned. The spoke bottomed out completely before reaching 100 kgf. The other 2 had too long or too short spokes, but could be tensioned... their initial build quality was terrible. Completely uneven tension, some over max tension, some basically loose. I cant believe anyone would ship out wheels in that condition...
Rear non drive leading spokes...sounds like the factory didn't put enough tension in the spokes when they built the wheel, and/or they didn't properly seat the spokes & stress relieve them. I'd say replace the last 3 NDS spokes, then check the entire wheel for proper spoke tension, true & adjust as needed, and properly stress relieve the wheel.
spoke breakage - next move?
I think you should keep riding the wheel that breaks each time you ride it. And when a big wind blows on your face, spit into errrrrrr never mind. Re-lace the rim ....is what I'd do.
I should've put this in my initial post, but the wheel is about 2 years old so it'd be hard to lay it off on a poor build. I think what got the breakage started was a stick in the spokes.
I've been stress relieving all the spokes as I replace the broken ones using Brandt's squeeze method, trying to get more to break. I guess my hands are weaker than my ass is fat if you know what I mean.
Sounds like I need to de-tension, replace those 3 remaining spokes, then re-tension, de-stressing as I go. Thanks for the info
I may or may not be laughing at you.
This sums up my thoughts and personal experience. Replace the the remaining three and retension the wheel. I'd also check tension with the tire on as the heavy bead stretch typical in Stans' results in a pretty significant tension reduction.
Originally Posted by aerius
By mountaindavis in forum Drivetrain - shifters, derailleurs, cranks
Last Post: 10-18-2012, 10:16 PM
By jhat in forum XC Racing and Training
Last Post: 05-30-2012, 12:15 PM
By brcjacks in forum 29er Bikes
Last Post: 04-28-2012, 04:58 PM
By PaMtnBkr in forum General Discussion
Last Post: 11-08-2011, 04:02 PM