I think the rim is defective, wobble or hop causing uneven tension.

Yes, Yes, Yes... Especially on some of these mystery manufacture hubs.

Another thing is the wheel set. After breaking multiple spokes on one set I checked the spokes. The whole wheel set was of of mystery manufacture. The spokes were around 15ga but less in diameter then 14ga. For me averaging about 240# I am sure they were stressed. My solution was to rub out a chamfer using a large drill bit by hand on the hubs as I replaced the spokes, one by one. The new spokes were 14ga Sapim. Fun, Fun, Fun...

This has been my favored source for spokes: https://www.bikehubstore.com/Sapim-R...leader-sil.htm

Further note: Having an extra wheel set is a real blessing. Think about it.

Could be. Better throw out the rim as well as the spokes!

And that hub. Seems suspect. Better toss that too.


This is all much better than getting the wheel trued.

A few thoughts.

Firstly AISI 304 or 18/8 or EN 1.4301 is a decent spring steel. One of the common uses for said steel is actually springs. One big reason why it isn't used for bicycle frames is it's price. Stainless steel in general is pretty expensive and even though 304 is fairly common stuff, it's still around the double the price of AISI 4130.

Secondly I went and looked at my wheels. It would seem that the need for seating the elbows is rare to the point of obsolete with today's wheel components. Even the lighter weight hubs I have still exhibit thick enough flanges that there is absolutely no need for setting the elbow or spoke head. With older steel hub shells exhibiting much thinner flanges it may have been more relevant. But even in those situations I'd rather use spoke washers.

Which brings me to my next point. Spoke tension should take care of any spoke path issues in due time. In fact a proper stress relief should also set the spoke paths pretty much immediately. I find it extremely unlikely that the spoke head would be able to spring out against 1200 newtons of DS tension and 700 newtons of NDS tension. We're speaking about 2mm steel wire that you can put permanent bends to with your fingertips. When we tension the wheel, the spokes experience elastic deformation. It just simply isn't possible that you'd have a floating piece of spoke flexing against the pull of the spoke while you're still having the spoke stretch for sometimes more than 1mm or so (for very long at least)

What I suspect is happening is along the lines cyccocommute wrote earlier. If I refine a bit, when a wheel is built and the component selection is done badly (ie. the flanges are thin and spoke elbows are long and no spoke washers are used) and no stress relief is done or it is done to too low of a degree, the elbows may remain "floating" away from the hub flange. Tension will however, in time, pull them into submission against the flange. Depending on how far outside the elbows are, the subsequent bending against the flange would effectively lengthen the spoke which can drastically drop the spoke tensions of the wheel, which would then logically lead to spoke failures if not addressed.

So to conclude, I believe that these days spoke head or elbow setting is necessary only when there's some inherent incompatibility with the spokes and hub. However the same effect could be achieved with spoke washers. With most modern aluminum hubs and DT Swiss spokes (I've ever only built with DT Swiss) spoke head or elbow setting simply isn't necessary since the spokes adopt a perfect path against the flange when the wheel is properly tensioned.

He’s got it in his head that stainless steel is some how “soft” or “weak” as compared to mild steel. It’s based on a very old myth that says the carbon steel spokes are somehow better material for spokes because…reasons. Here’s an article on stainless steel as spring material.

I do it because it reduces possible variances in the spoke tension over time which lead to the problems you outlined. It can also be part of the stress relieving process. Side bending of the hub, i.e. setting it on the floor and bending the hub down, is part of bending the spokes to the hub. Prebending them by forming the spoke to the hub does this before tension is even applied. I haven’t side bent a wheel ever during a build partly because Hjertberg has said not to do it. Even in the article that taught me how to build wheels written 40 years ago, he was advising against side bending

You have built how many wheels? I have built hundreds. The people I have worked with have built hundreds, and the people they learned from have built hundreds or thousands of wheels. All of those people use the same basic set of techniques on all thoroughly modern equipment - not steel hubs. All of us agree on these basic principles, as will any wheelbuilder you care to find. And all of us have seen the kind of elbow failures being discussed on equally modern equipment, and have SOLVED those issues with the techniques discussed. Because machine built wheels commonly have a poor spoke to flange contact, and we have seen that many, many times.

There aren't any "thin flanges" and spoke head washers in modern wheels. All of these dimensions were worked out for alloy hubs decades ago.


I, as a representative of the professional wheel building industry, am trying to relay to amateurs how this stuff works and why. I am extending the courtesy of sharing those things the best I can in the face of a lot of objections that are fun to talk about, but are basically the theories of people with little to no real experience or education.


So this situation is analogous to going to your doctor and arguing about the power of crystals to cure cancer. I don't care what you think you've learned building a handful of wheels, or by reading a metal chart. The basic facts remain the same, and you are wrong. Any pro builder that says that spoke elbow seating is unnecessary would be a fraud - but basically such a professional doesn't exist. Everybody paid to build wheels professionally does it and teaches it because it works.


Or you can take the word of the guy who has broken tons of elbows not setting them, and is therefore convinced elbows are delicate and every wheel needs 2.3mm elbows. Even though we know good wheels don't break elbows. Even though being the "go to" guy at a coop is like being the most handsome carnival worker.

You don’t read so well do you? I explained why spokes are preformed to the hub and you said it was BS. I have never said that I don’t set spokes. I have broken tons of spokes despite setting them. You’ve claimed that I practice magical thinking but relying only on setting spokes and tension is equally as magical.

As to the co-op, professional mechanics on these forums use that as an ad hominem all the time. Here’s a clue: A 15 year old kid can be called a “professional” mechanic but he knows nothing about bicycles at all. How many bicycles have you worked on in the last 15 years? I’ve worked on north of 20,000…52 times a year, 6 work stands at a time, 6 hour shift, pushing through 30 people per day for 15 years. And the vast majority of those bikes have been bikes that shops won’t fix. In addition to that I teach classes on how to fix bikes and I teach people…including the professional mechanics on the retail side of the co-op…how to build wheels. I am not an amateur. The only difference between me and a very old mechanic is that I give away my knowledge and expertise rather than take pay for it.

And, on top of that, I’m a professional scientist who goes and investigates something before shooting off about it. Things like stainless steel being a pretty good spring material and how spokes are formed and the science behind why we do what we do in wheel building.

And, finally, if “we know that good wheels don’t break elbows” why are broken spokes a thing? Why are people, including SamSam77, always asking about it. Granted it’s not a problem for everyone but it is a problem for some and there are better solutions than saying “just increase the tension and bed the spokes”.

Let me illustrate what it is like posting on these boards with a lot of training and professional experience:

Recently there was a thread about how DT had made some change to its nipples and that the new dimensions required using the larger Park Green spoke wrench instead of the Black one we've all used forever.

Posters, some of whom mentioned their coop experience, quoted some online documents, posted dial caliper measurements of DT nipples and then weighed in very authoritatively that the Green wrench was the only proper wrench.

Now, I have somehow managed to use a Black wrench on DT 14g and smaller nipples forever, and so has everyone else I've worked with. That opinion was rejected.

So then I wrote the tech department at DT and received a definitive answer that their 14g and smaller nipples are a perfect match for Park's Black wrenches, and that at no time were Green wrenches an acceptable fit. But some amateur out there is probably convinced that's also wrong.


There is no arguing with the power of belief. It trumps experience, training, common professional practice and even common sense. This has become a societal problem, so I guess it isn't shocking that it applies to bikes as well.

But it's the reason there are so few of us that bother posting on the Mechanics forum. You guys go out of your way to undercut whatever resource of experience is being offered.

So someone got something wrong. It’s not like you’ve been absolutely correct on everything…see “stainless steel as a spring material”. People make mistakes. Frankly, I wouldn’t go on what anyone “said” about the size of spoke wrench needed but would go on the size that fits. On a wheel, no one can tell if the spoke nipples are DT Swiss, Sapim, or something made in India. It’s not like they have any kind of marking on them. I use Wheel Fanatyk splined spoke nipples so I can tell what brand they are and I use the appropriate spoke wrench.

That may be true if someone doesn’t have experience and/or training. I’m not an inexperienced noob. I have cited other people who are professional wheel builders that agree with what I’ve observed over more than 2 decades. Other mechanics have chimed in that spoke breakage is a problem with their shops. I’m not pushing out pseudoscience but I try to back up my information with other sources.

Perhaps the problem is you! You are being a Cartman, shouting at us to “respect my authoritaaa!” Your (and my) threads usually devolve into you making insults along the lines of how I’m just some idiot in a co-op that knows nothing. You can disagree with me all you like. I’ve got thick skin and been doing this a long time. Please extend me the curtesy of disagreeing without being insulting. I may not know everything but that doesn’t mean I know nothing.

You are usually the first to insult and the more insulting one. You are usually the first to bring up your authority as a chemist. You're calling the kettle black.

And then you always mischaracterize what I say, like when you said "just set the spokes and tighten them". That was not my advice. And that is why I try not to go point for point with you, because you distort what is being said, as you have multiple times in this thread. It is dishonest.

There's a few problems here. Firstly (and I'll address this again later) your argument seems to be purely a claim to authority, which isn't an argument but a fallacy. Million flies can't be wrong, pile of... You get the idea.

From what I'm understanding from your post, at some point someone of your old expert professionals mistook correlation for causation without considering the actual cause for elbow breaks. If said person was loud enough or had enough clout, the mistake was then elevated to be a part of cycling lore. Ie. it's a myth perpetrated by people who believe their mentors explicitly (you really shouldn't do that. Question everything).

If the spokes keep on breaking at the elbows, that doesn't mean not insufficient mythical processes were performed for the elbows. It means the elbow is somehow special compared to the rest of the spoke and if a spoke breaks, it'll break at the elbow. The elbow is bent whereas the rest of the spoke isn't. It is is a stress riser. Steel in tension tends to break at stress risers.

If we employ Occam's razor and consider the simplest possible reason why spokes break at the elbow, it's because of the stress riser thing. Not because of spoke path.

That being said, there are other stress risers on spokes. Breaks may also happen at those places. But the elbow is a good assumption for breakage, if a spoke is to break.

It doesn't surprise me that there's a lot of this mythical stuff in wheelbuilding. There was a person who once wrote about compression of spokes. Regardless of what he meant, it was extremely badly communicated and those ripples cause confusion even today.


Actual professionals should have white papers, studies, schematics, technical drawings, material charts, manufacturer documents etc. to use as evidence instead of claims to authority to surpass any and every objection. The technical professionals I work with typically never make a claim if they don't have something concrete to back it up.

I've actually been a PRO mechanic one time. I don't flaunt it because it counts for nothing. As to the rest, my doctor wife would be very amused. The medical profession is heavily evidence based for a reason. Crystals have been studied. There are papers showing they don't work. But the medical field doesn't as a collective believe that an increase in ice cream consumption raises the risk of drowning even though there is correlation between the two.

There are things in Cyccocommutes methods I don't agree with but this isn't one of them. He does actually set the elbows. But the reason he does it is because it speeds up the build process and makes the wheel less failure prone after it goes out the door to someone who doesn't know how to adjust wheels. I don't do it because I can take my time building and I can adjust them after I've ridden them a while (I don't actually need to though).

But aside from all of the above, if the elbow is such a risk position, shouldn't we build all wheels with straight pull hubs and spokes? No elbow, no problem right? Straight pull spokes should make a practically indestructable wheel. But we know that straight pull spokes do break. What is up with that...

Let me cut to the chase:
I said I have seen elbows that are not conformed to the flanges, as have my associates. And you are calling us liars.

It isn't "authority" when you are the witness and practitioner of the information presented. I'm not an expert about something, I am the first person source of the information.


So I didn't read all of this. In the face of the fact that you think I'm a liar, there is nothing to discuss.

But saying that setting the elbows is such an extreme extra step that only straight pull spokes should be used is frankly idiotic. Or it means that you don't know what we've been talking about: It's pushing the spoke in with your thumb.

Calling someone a liar and calling someone mistaken are two very different things.
I haven't disputed that you or your associates have seen elbows which haven't conformed to the flanges. I have disputed the significance and the arguments you've provided for reasoning said significance.

Now I'll probable regret this because I think I know what you'll answer (if you do answer) but with the wheels you've seen where the spokes haven't conformed to the flanges, have you or your associates by chance done a comprehensive analysis of the wheel and the spoke tensions? And if yes, what were the findings?
Could it be in the realm of possibility that if the elbows haven't conformed to the flange, the issue with the wheel is not in fact setting of the heads but instead insufficient tension and/or stress relieving?

Sadly there aren't many studies into wheel dynamics or the significance of various factors that go into building a wheel. That doesn't however change the fact that anecdotes aren't evidence even when they're being presented as fact via claim to authority.
If what you've been taught isn't written and published, isn't tested objectively, isn't reviewed by others, it's not really all that meaningful or relevant. Even the publishing thing with enough analysis of what is actually going on would be sufficient for discourse. But when you pull such big claims and just expect people to believe you unquestioningly because you're a pro who was trained by pro's, well. It's meaningless.

Suit yourself. But don't go claiming the moral high ground and pull the pigeon chess maneuver when you've misunderstood what you've read.

You came out swinging with the argument that wheels pop spokes because the heads / elbows haven't been set properly. If it is something you can do with the press of a thumb, it is something 1000 newtons of force will also pull in line.
It is simply not feasible that when one misses a thumb push the wheel begins popping spokes left and right when we consider the forces involved in a bicycle wheel.

You'll need to quote me the studies and white papers that lead you to your various conclusions. Until then, you are the inexperienced doubter and I am the one correctly practicing and observing a trade craft for four decades that started with the studies at Wheelsmith.

And not like some monkey following directions, either. I had the top SAT score in my high school, went to the number ten university in the US, had a successful career as military and commercial pilot, investigated aircraft crashes and got into Mensa. I have thought an awful lot about why some things break and why even damaged elbows don't, and the fact that I can fix a wheel that is breaking spokes by simply manipulating the bends and tensions tells me that the people like you that "know better", don't.

You have never done any of those things with wheels, and simply aren't qualified to have an opinion. It is tiresome, and screws people who need help out of useful advice because the armchair brigade takes the useful advice and hides it in the noise.

One thing that is perhaps being misunderstood is the difference between plastic and elastic deformation and spoke elbows.

Elastic deformation is when you flex something, and it springs back. You can do this with spoke elbows - flex them via tension until they contact the flange. This puts the bend under tension, like a preloaded spring, and that sprung elbow is going to react to tension variations from rolling by subtly changing shape. Essentially, it will try to curve away from the flange when the spoke nipple is pointing to the pavement, and flex back as the tension goes back. These cycles work harden the point on the elbow that changes shape the most. And you can observe this in used wheels as the spoke elbows backing away from the flange as tension goes toward zero.

Plastic deformation is when you flex something far enough that it no longer springs back. Anyone who has cold set a steel frame from 126 to 130 dropout spacing knows that to get to 130 you have to flex the frame well past that point until you actually deform the metal. Once deformed, the new shape of the frame is a 130 with no tension or force holding it there. That is what elbow setting is - deforming the spoke permanently to a new elbow bend that matches the flange contour. Once that happens, the spoke elbow does not change bend shape as tension is applied or removed, there is no spring effect at the elbow and it does not work harden from the cycles of road contact.


You can't see whether a spoke elbow is flexed or actually deformed until you change the spoke tension, unless the flange geometry and spoke stiffness are such that it never conforms to the flange despite full tension. I have observed both situations.

If you say so. But you haven't actually provided any mechanical analysis about your claims. Just claims to authority.

So you've been a bike mechanic for four decades, been a military and commercial pilot and been a crash investigator? You've certainly gotten around. How does one combine the rigors of military aviation and a career at the bleeding edge of bicycle mechanics?

I mean, you don't actually know what I've done and what I haven't. I could be an astronaut who fixes bikes in jupiter. You need strong wheels in that sort of gravity...

How is the elastic deformation of the elbow different from the elastic deformation of the spoke? We want the spoke to elastically stretch. It's one reason why butted spokes are better since they stretch more than straight spokes at the same tension.

The answer: it's not different.

Elastic deformation does not work harden. Plastic deformation work hardens.

But again, since elastic deformation does not work harden the spoke, why does the spring of the elbow matter? Especially if the elbow is held in position by tension?

If anyone believes that spoke tension alone is sufficient to cause plastic deformation of the spoke elbows, here's a fun test you can perform today:

Loosen a high tension spoke in one of your wheels until free of the nipple (don't let the nipple fall into the rim!). Mark that spoke with tape or a marker. Around mid spoke, use your thumb and fingers to put a soft 30 degree bend in the spoke. Thread back into the nipple and re-tension. Now undo the spoke - is the bend gone?

Put the bent spoke back into tension and perform stress relief on the wheel, focussing on really working that bowed spoke, essentially working the spoke via even higher tension to stretch that bend out. Undo the spoke again - did the bend go away? Straighten the spoke with your fingers and re-tension.



Spoke tension is not enough to cause plastic deformation. Which is good, because if it was, the spokes would stretch over time - or simply fail. The typical 100 to 120 KgF tension puts the spoke in a state of elastic deformation - it stretches the spoke impermanently in length (much like a QR compresses an axle impermanently). But if the spoke does not conform to the flange profile already, it will also elastically deform at that bend - something the spoke doesn't like as much because it is so localized compared to elongation across the entire length.

I thinks you all are turning into uncouth hacks!

There are essentially two ways to set the spoke, or deform metal generally:

Bending past the yield point. This is what I do building wheels, because it is simple and quiet. If the spoke needs 20 degrees of bend, you bend it maybe 50 degrees and it deforms to about the 20 you wanted. The reason for the way this happens is that the elastic deformation never stops happening, even after the plastic yield point is reached. So the spoke has to be flexed enough to spring AND bend the spoke at the same time. This method is not exact, though you can make each of the bends equal to each other. The precise amount of bend is less important than just getting the elbow to an angle where it seats against the flange before there is any real tension.

Bending can be done during lacing or after, since untensioned wheels have a fair amount of slop in the spoke length to push laterally.


The other technique is impact. This is the method Sheldon Brown promotes. It is arguable somewhat precise, as it uses shock to 'cold forge' the bend to the shape of the flange on an already tensioned spoke. This is the technique I use on a wheel I suspect was never seated, and I am not going to zero the tension out and come back up. Aside from the noise and extra tools required (I use a mallet), I don't like to do it to new wheels out of respect to the customer's hub flanges, since smacking the spoke uses the aluminum hub flange as an anvil, and aluminum is not good anvil material. Does it matter? I doubt anyone has ever been able to study what long term effects it has on later flange failure - so do whatever you want. Mine is just a preference.


In my experience, a quality machine built wheel that has broken a few spokes at the bend will stop breaking spokes if the existing ones are set with a mallet and then the tensions are evened out and put in the proper range for the kind of spoke and the number of spokes on the wheel. (Higher spoke count wheels should use less tension per spoke as the total wheel tension matters, and higher tension puts more localized strain on the rim's nipple holes. No reason to strain a well supported, high spoke count rim for no reason.)

It may be that simply correcting the sprung bends is enough to buy a lifetime of fatigue resistance, which might be born out by the observation that even chain damaged spoke bends seem to survive ordinary use. If bends, regardless of being sprung, were major stress risers, damaged spokes would break all the time. And they don't.

Or, it may be that striking the spokes with a mallet not just deforms them, but stress relieves them, resetting the grain and removing a portion of the prior fatigue. Someone with a lab could do that sort of analysis, but it really isn't important. I also blacksmith knives, and it is often said that striking the anvil next to the work object stress relieves it, but I have never bothered given all the heat cycling.


So anyway, if you are breaking elbows, get someone to smack those bends and re-tension with stress relief. In my long professional experience, the spoke breakages will stop right there and no new spokes will be necessary.


On tension, the most important thing is uniformity rather than a particular tension. So use a tensiometer to get in range, then fine tune tension by tone, like a piano tuner. Your ear is more accurate than the collection of pivots and springs in a mechanical tensiometer. Perfect uniformity is usually not possible while achieving a straight rim, but uniformity allows you to see how to shape the rim with multiple spokes having influence over the same rim section. You can have a very straight rim with very uneven tension - especially stiffer modern rims.

Kontact gets bonus points for this section. His analogy makes sense to virtually no one, except his intended audience.

To take the analogy further, you can't tell if a frame has been cold set to 130 until you take the wheel out. It might bend every time you force the wheel in, or it might not.

Springing metal does not mean that 100% of the deformation is elastic. Otherwise spring set wouldn't exist.

There is a popular myth that springs don't wear out, promulgated by people that read rather than do. A sprung elbow is not a well designed spring.


Anyone who has seen a worn out steel frame (usually a failure at the right chainstay a few inches from the BB), knows that steel does fatigue from work cycles that fail to measurably bend it.

Ha! That's it! Last year I rebuilt a wheel set with better quality Sapim 14ga spokes. I have been totally satisfied with the rebuild and then noted loose spokes a few months ago. I have been totally perplexed. Across all the spokes, all were moderately loose on the rear wheel. When I top off the air in my tiers I routinely ping the spokes for changes. With all the spokes getting evenly loose the pings did not really change. I should have Formed the spokes at my rebuild and from now on I'll use the Squeeze Technique to check their tension at each airing... Thanks...

Except it won't necessarily occur naturally. The elbow might fail instead.

... meanwhile.. Sam bowed out of this mess over 60 posts ago.

i hope he got the issue sorted out.... and several still here need to get their issues sorted out .:fight: