Originally Posted by
TiHabanero
Shelbyfv, I have posted a few times on this subject and have yet received an answer. What brought it up this time was a discussion with the service manager at the shop where I work weekends. He insists DB spokes are more durable and resist breaking better than straight gauge. I asked him for proof, which of course he did not have. I suppose this has to be laid to rest, and I will have to simply turn the other cheek when I hear the proclamation of the virtues of DB spokes.
I think a lot of these discussions go into the weeds because the benefits aren't stated accurately. A 2.34mm straight-gauge spoke by itself is obviously way stronger than a DT Revolution. The spoke strength chart at the back of Jobst's bike actually shows that straight-gauge spokes can be pulled to somewhat higher tensions than butted spokes of the same end thicknesses.
But with bikes, we like to optimize things. Straight-gauge spokes tend to break (if/when they do) at the ends, meaning that there's more material in the center than necessary; the ends are the weak links. So it's logical to think that if you put extra material on the ends and took it away from the middle in just the right amount, you'd end up with a spoke that is equally durable from end to end. From there, you'd scale the whole thing up or down according to your needs. (My rando bike wheelset is an experiment in scaling down -- 4300 miles so far on 32/3x 1.8/1.6/1.8 and I'm wondering if I could have pushed it further!)
Given the question of how straight-gauge spokes don't seem to break a lot more even though they are more likely dip to zero tension at the bottom or when hitting potholes, I think the extra material compensates to some degree. Plus (per Jobst), spokes carry load in proportion to their tension, so I think that's another way that life isn't as hard for NDS spokes as one would imagine.
So if the extra weight of straight-gauge spokes doesn't bother you
or cause problems, the world is your oyster. They're cheaper and easier to build into wheels. People ride many thousands of happy miles on straight-gauge spokes without being aware of it.
