Sapim Strong: Broke yet another spoke

[redir]

The wheels are an older set of Neuvations that I have had chronic spoke failures on since day one. It's the rear wheel on the drive side. I even sent them back to be rebuilt and then sure enough after about a month I start hearing this creaking sound and another two rides or so later and Ping! Broken spoke. I am 200lbs and these are 24 spoke wheels but I think the design is just shiddy so they keep breaking.

So I googled up "strongest bicycle spokes" and it appears that the Sapim Strong are at least this companies strongest offering. Interestingly I have always been told that double butted spokes were the strongest and these are merely single... but alas.

My idea is to buy 12 Strong spokes and rebuild the drive side of the wheel by removing one spoke at a time and truing up. Does that sound feasible? These are carbon hoops some 30mm deep or so, so they are pretty stiff rims.

[unterhausen]

Do you know what brand of spokes are on there now?

I always just rebuild the whole thing.

[redir]

Originally Posted by unterhausen

Do you know what brand of spokes are on there now?

I always just rebuild the whole thing.

I don't. They seem to be unmarked. I may have to take a better look. If I were to rebuilt the whole thing does the concept of one spoke at a time and truing up make sense? It seems like it would work to me but intuition is often wrong.

[RudAwkning]

Originally Posted by redir

The wheels are an older set of Neuvations that I have had chronic spoke failures on since day one. It's the rear wheel on the drive side. I even sent them back to be rebuilt and then sure enough after about a month I start hearing this creaking sound and another two rides or so later and Ping! Broken spoke. I am 200lbs and these are 24 spoke wheels but I think the design is just shiddy so they keep breaking.

So I googled up "strongest bicycle spokes" and it appears that the Sapim Strong are at least this companies strongest offering. Interestingly I have always been told that double butted spokes were the strongest and these are merely single... but alas.

My idea is to buy 12 Strong spokes and rebuild the drive side of the wheel by removing one spoke at a time and truing up. Does that sound feasible? These are carbon hoops some 30mm deep or so, so they are pretty stiff rims.

What's the cross pattern on the spokes?

[redir]

Originally Posted by RudAwkning

What's the cross pattern on the spokes?

I'll get a pic later. I think they are just 2x.

[RudAwkning]

Originally Posted by redir

I'll get a pic later. I think they are just 2x.

Also, where are the breaking? At the bend? The Nipple?

[redir]

Originally Posted by RudAwkning

Also, where are the breaking? At the bend? The Nipple?

This last one was at the J-Bend. I cannot honestly remember the others. But I have probably broken 4 spokes on this set in ten years and I really don't use these much. In fact I relegated them to my cyclocross pit wheels.

[FlashUNC]

Aren't Neuvations rather notorious for spoke breakage of all sorts?

[GOTHBROOKS]

i just placed an order for a custom wheel build and was on the fence about the sapim strongs but went with the sapim leaders because in the end i was afraid of my wheels being “boat anchors”.

[DfCas]

Are the existing spokes straight guage or butted? Butted spokes are not stronger, but they tend to break less.

[oldpotatoe]

Originally Posted by GOTHBROOKS

i just placed an order for a custom wheel build and was on the fence about the sapim strongs but went with the sapim leaders because in the end i was afraid of my wheels being “boat anchors”.

64 Sapim Leader spokes(straight gauge) are 431g...64 Sapim Strongs are 446g...15g for 64 spokes.

[calebrichardson]

If a spoke breaks at the J-Bend, I would replace all the spokes.

Individual spoke defects are pretty rare, spoke breakage at the J-Bend is typically due to low tension and load cycling. This means that if one spoke broke, the other 11 are probably pretty close to breaking as well. Furthermore, since non drive side spokes are at a lower tension than drive side, those are probably close to breaking.

Load on each spoke is reduced by a higher spoke count, stronger spokes (marginally), and a deeper/stronger rim.

Plenty of people at 200lbs on 24h spokes, but I think most wheelbuilders would recommend 28h unless you are on 45mm+ carbon rims.

[AngryScientist]

Spokes break for a reason. There is a good chance the rim is "sick" in some way and any spokes you build them up with are going to have issues.

i had a set of neuvations way back when and they were more or less junque. i would politely suggest just moving on.

[Mark McM]

Spokes don't just break by themselves, there are usually other factors involved. Based on the short life after the last rebuild, I'd be wondering if the rim isn't bent. If it is bent enough, you won't be able equalize the tensions, and if some of the spokes are too loose, it will concentrate the loads on the tight ones, which can lead to premature failure.

The rim could have been implicated in the earlier failures as well. The spokes don't support wheel loads by themselves, the rim has to be able to distribute the loads amongst many spokes. Stiff rims distribute loads around the wheel very effectively, so with a stiff rim you don't need many spokes. A 200 pound rideer should be able to get by with 20, or even 16 spokes, if the rim is stiff enough. But a flexy rim can't spread the loads very widely, so the spokes need to be closer together - in other words, you need more spokes with a flexy rim. A flexy rim with a low spoke count is a recipe for spoke breakages.

Another place to look is at the spoke/hub interface. The elbow of the spoke should be snugged tightly against the flange, to distribute loads evenly across the elbow. If the spokes fit too loosely in the flange holes, it can introduce bending loads, and concentrate the extra stresses at the small contact point.

In regard to previous comments: As noted, "strong" and "durable" are the not the same thing when it comes to spokes. Thin, butted spokes will be more durable than thick straight spokes. Spokes break at their elbows or threads. The thin center sections of butted spokes are stretchier, and this extra "give" reduces the loads transmitted to the elbows and threads. Thick spokes are stiff and have little give, and transmit more load to the elbows and threads.

As far as spoke pattern and number of crosses, this is often talked about, but in reality lacing pattern plays little role in spoke stresses. Henri Gavin, a professor of engineering at Duke University, instrumented the spokes in several wheels with strain gauges, so he could measure the stresses in spokes as they were ridden. The wheels used identical components, but different spoke crossings. He found that the number of crossings played an insignificant role in the cyclic stresses which cause spoke fatigue.

[prototoast]

Don't throw good money after bad. Neuvation went out of business more than 7 years ago. So you've got old hubs, old rims, too low a spoke count for your weight, and chronic spokes breaking.

Just get a new wheel.