Originally Posted by
dabac
The theory is clear that the NDS spokes should have it worse.
But sure, I bought my first freewheel puller to deal with a broken DS spoke, not to replace the f/w. It does happen.
I’ve sometimes wondered if it’s possible to build a wheel with low enough tension so that the NDS spokes survive b/c of never seeing enough tension to fatigue, while putting the DS spokes right in the fatigue range.
And there’s always the option of the really sloppy build where some spokes simply started out a lot slacker.
Last IGH I built up had an 8% difference in spoke tension between DS and NDS. Last derailer gear wheel I built had about 60% NDS spoke tension.
As someone already wrote, what breaks spokes is constant bending, the frequent (big) changes in tension that causes metal fatigue. It’s far easier to get all spokes into the ”safe” zone on an IGH or otherwise near symmetrical wheel. For a comparable build quality, no mystery there.
"Not enough tension to fatigue" is a contradiction in terms and actually the opposite of what fatigues a spoke. High tension results in less fatigue. Spoke fatigue occurs fastest with low tension in a wheel. When a spoke with low tension goes to zero with each wheel revolution, it fatigues quickly and breaks. This explains why a lot of times, NDS spokes fail first. This also explains why people have issues with spokes loosening. If a spoke reaches zero tension through the rotation, it allows the nipple to turn ever so slightly with every rotation. Eventually the spoke is noticeably loose.
So, counter to some people's intuition, high spoke tension is NOT the cause. It's low tension and a dished wheel. And straight-guage spokes. And low spoke count.
Yes, you want a beefier wheel built for your usage. Rear wheels have two major factors reducing their durability:
1. Dish. Half the spokes are doing most of the work. 12 speed hubs have even more dish, worsening the problem.
2. Approximately 60% of your weight is on the rear wheel.
So you want a clydesdale-type rear wheel. In general, you increase rim width/strength first, then spoke count. But you also want THINNER spokes - in the middle, that is. Contrary to intuition, a FATTER spoke will not build a more durable wheel. A butted spoke will. Ideally, you may want to go with a 2.3/1.8/2.0 spoke. This is the "Strong" spoke in the Sapim spoke line. I think DT offers something as well.
So a heavy, wide, strong rim with 36 spokes (if you can find it), and with asymmetrical drilling (to reduce dish), butted 2.3/1.8/2.0 spokes with brass nipples built by a proficient wheel builder who can guarantee very even spoke tension should solve your problems. Locking nipples too (or at the minimum, appropriate thread locking compound and lubrication). No wheel is indestructible, but this is about as close as you can get. This would be a good choice for a clydesdale or tandem.