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A friend and very reputable wheel builder built me up some wheels about two years ago. They were Kinlin hoops (don't remember the model) with Novatec hubs and had Sapim spokes (28 rear, 24 front).

About 6 months later, I broke the first spoke in my 10 years of riding. I was 190 pounds at the time. He fixed it for me and checked all the tensions and about 6 months later, it happened again. Both front wheels and both broke at the hub. This time I got someone else to fix it and he said the tensions were too high. A few months later (Thanksgiving week) it happened again despite the fact that I'm 175 now.

I finally said 'to hell with it' and ordered me a set of Vuelta Corsa Lites. So far, so good. Still puzzled at why those wheels gave me so much trouble.
 

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Could be several things but probably is just non-equalized tensions. If the tensions are not equalized at the builder's table, they try to self-equalize under use and every time there is an impact. The end result may be a spoke of two that loose adequate tension to keep things tight. When this happens the spoke eventually breaks at the elbow.

I dont think the higher tension value caused the spoke to break at the elbow if they were uniform around the wheel. If anything it would have caused the rim to bulge around the spoke hole.

Lastly, 190 lbs and 24 spokes dont make for a wheel focused on durability. So it is what it is.
 

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changingleaf
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It doesn't look like it's the fault of the build. It's most likely a defect in the spokes. I had one wheel give me trouble similar to that and it was built like all the others, but apparently with a bad batch of spokes which is exceedingly difficult to determine. At the time I had only a small number of those particular spokes in that specific length used for that particular wheel and they were not used on any other wheels so without a microscope that was my best determination, and I replaced the spokes.

Here's some more info on spoke breakage.

Spoke Breakage - Getting Real - Wheel Fanatyk
 

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It was 24 in the Front and 28 in the Rear, so "should" have been adequate depending on the OP's riding style and the roads he was on. He broke spokes on the Front wheel which typically doesn't happen if the wheel is built correctly and its components are all sound.
 

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Do you have any pictures of the hub area of the wheel and that of a broken spoke, and even better of what's left of the broken end of the spoke?

It could be a bad batch of spokes, but that's not overly common. But if the failed spokes are outbound (heads in), then I'd also be suspicious of a combination of the builder having forgotten to seat the spokes and insufficiently tension. This is usually a bigger problem in rear wheels. An unseated outbound spoke, and especially if insufficiently tensioned, will flex at the bend as it enters the hub hole. Over time that flexing will cause the spoke to break at the bend.

Over tensioned spokes will typically result in rim or hub flange failure long before spoke failure - at least with normal SS spokes. Increasing tension will not save spokes that were bad to begin with or had experienced too much prior flexing at the head.

Regardless of whether it was a bad batch of spokes or a mistake during the initial build, given you have had 3 spokes fail already, you need to replace all the spokes in the wheel, as the remaining spokes are either defective or have become weakened.
 

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Had the same thing happen to a front wheel with CX-Rays some years ago.

Sapim of course denied any responsibility but later I heard from other people having the exact same problem. Likely they let out a bad batch of spokes.
I moved on to DT Swiss and Hoshi and never bought another Sapim spoke.
 

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Ron Ruff built me a set of wheels in 2007 using black CXrays and two of those in the rear broke. I sent the entire wheel back to him and he respoked it because he said at that time Sapim had a bad run of spokes. I still ride it today.

I have another set of wheels from that same year, built with the same hubs, rims, and Silver CXrays......they have never had any problems. Could have just been the black spokes with the issue at that time. I now build my own wheels and use CXrays almost exclusively. So far, no broken spokes on wheels I have built.
 

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I'm surprised it's a front wheel spoke. I've built countless wheels for myself and my friends and NEVER have broken a spoke, no have my friends.

And I don't think my skills had a lot to do with that success rate.

Front wheels see no torque loads like rear wheels do, so they last much longer.

While enough people here have already singled out Sapim having a bad batch of spokes that you could conclude that was the cause, I'll also suggest a poorly designed hub.

If the alloy is wrong or the flange too thin, it'll cut into the spoke and lead to premature spoke failure. But try different brand spokes, first.
 

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It doesn't look like it's the fault of the build. It's most likely a defect in the spokes.
Agree. While uneven spoke tension can be a breakage cause on rear wheels, it is much less likely on front wheels and would tend to cause the wheel to go out of true. People make way too much out of which way the spoke head sits and prestressing the wheel, particularly when talking about front wheels. Uneven spoke tension can be easily checked just by "tonking" the spokes with a screwdriver blade and listening for the tone.

I agree that 24 spoke front wheels are not a great choice for a 195 lb. person but the fact that there is front wheel spoke breakage while none on the rear points to bad spokes.
 

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We can speculate as much as we want but sight unseen and actual history unknown we will never pass the speculaton stage on why the front wheel spokes keep on breaking.

Noone can exclude manufacturer defect as the cause but, equally so, noone can dismiss the build quality, or lack of, either especially since it should be obvious that the wheel is underbuilt for continous use and it has been built/corrected? with probably uneven "too high" spoke tensions as the OP was told by the 2nd builder.

Interestingly enough, the 2nd builder, after seeing the conditions and history of the wheel, did not suggest to the OP that under the circumstances a total rebuild was warranted. Some of us may have witnessed how truing an existing wheel often happens between customer walk-ins and phone calls. Ending up with "too high" tensions on a few spokes is not that rare. After a certain point in uneven tensioning there is no real recourse other than redoing the entire wheel.

Too many coincidences for me to emphatically chalk this under "manufacturer defect" but you are welcome to it if you so desire.
 
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