Straight vs. butted spokes

[dawgie]

I'm planning to order a new wheelset for my commuter - touring bike. However, I am getting conflicting information on whether I should use butted or straight-gauge spokes. Some sources say straight spokes are better for carrying loads, others say butted spokes are just as strong and ride better. Needless to say, I am confused.

Here's some background. The wheels will go on my touring bike that I use mainly for commuting. I weigh about 195 and my bike usually weighs about 30 lbs. when loaded with water, supplies and gear for commuting. I may do some occasional loaded touring on the bike, most likely weekend tours with relatively light loads.

My bike now has 32H Open Pros laced to Ultegra hubs. I'm running Michelin Pro2Race 25 tires, which measure more like 27s, but have some Panaracer Pasela 28s to install when the P2Rs wear out. I've ridden about 5,000 miles on my existing wheels with no problems. Never broke a spoke or needed truing in two years. However, I fear that I might be pressing my luck with the 32H wheels if I try some loaded touring. That's why I thinking about ordering the 36H wheels using Sun CR18 rims and Ultegra hubs.

[dvancleve]

AFAIK, straight gauge spokes are cheaper and 14g are easiest to build with. Otherwise butted spokes (14/15g anyway) are better all around. They are lighter of course. They have the strong elbows of a 14g spoke but are more resilient due to the thinner middle section and therefore put less stress on the spoke holes. From what I've read, straight 14g spokes are (more) likely to cause cracks at the spoke holes. For a basic, sturdy wheel 14/15g are the way to go. One thing I've wondered about is why straight 15g wouldn't be fine for the non-drive side in back (since it is much lower tension than the drive side) and maybe the front wheel. The elbows don't fit most hub flange spoke holes as well, but those tiny brass washers fix that.

Doug

[dawgie]

Here is why I am confused. I've had two different mechanics with 25+ years of experience tell me that straight-gauge spokes are stronger, particularly for heavier riders. Also, the builder I contacted recommended straight-gauge spokes, although he also carries butted spokes.

[cmg]

straight gage spokes are easier for him to build with and the added bonus is that they will also build a strong wheel for the lowest possible cost. nothing wrong with that...........but you could build a lighter wheel that will feel better to you but would be more difficult to build for him, take more time and need to be more precise in the tensioning of the spokes, require a re-truing after break-in (200 miles), if you build with butted spokes. It's what you want that matters. go the butted spoke route. 32 spokes will be enough, consider using lighter spokes on the front, but 14/15 would be cool.

[Pete Serotta]

Give Joe Young a call ....he is in Tx. Been building a long time and is excellent. Give him your needs and let him decide.

[shiftyfixedgear]

I believe Sapim used to make a single-butted spoke with a thicker 14g section down at the elbow and 15g up top.

They're perfect for people who get conficting "expert" opinions such as on the internet.

[gman]

Built and tensioned properly, both will serve you well.

The wheels built with 14g will be a "stiffer" wheel with less ability to absorb shock. They will flex less under load and will be extremely durable.

The ones built with DB 14/15 will take a bit of the edge off the ride and will be a bit lighter.

I weigh in at 230 and my commuter bike has 32h 3x 14g DT spokes which I built. It has nearly 8k miles on it and I have trued it maybe twice over the last 3 years.

The wheels I built for my new HSG have are the same build, but with 14/15 DT spokes. Same tires - Conti Gatorskin 25's and the latter are noticeably more comfortable and lighter.

[Ozz]

My take from Jobst Brandts book was that because the middle section of a butted spoke is more flexible (cuz it is thinner) it moves the stresses of flexing away from the spoke elbow, which is the weakest part of the spoke, to the center section of the spoke which is although thinner, is stronger because there is no bend.....of course this could all be hooey.

:beer:

[RPS]

From the late Sheldon Brown:

"Double-buttedspokes are thicker at the ends than in the middle. The most popular diameters are 2.0/1.8/2.0 mm (also known as 14/15 gauge) and 1.8/1.6/1.8 (15/16 gauge).

Double-butted spokes do more than save weight. The thick ends make them as strong in the highly-stressed areas as straight-gauge spokes of the same thickness, but the thinner middle sections make the spokes effectively more elastic. This allows them to stretch (temporarily) more than thicker spokes.

As a result, when the wheel is subjected to sharp localized stresses, the most heavily stressed spokes can elongate enough to shift some of the stress to adjoining spokes. This is particularly desirable when the limiting factor is how much stress the rim can withstand without cracking around the spoke hole."

[Peter P.]

Don't bother spending the money on special wheels. Yeah, the rims are kinda light, but wait until they wear out to replace them with something like Mavic Open Sport rims or MA-3s.

For your usage, don't bother concerning yourself with lightweight, double butted spokes. For all practical purposes you won't notice a difference. Straight gauge spokes are cheaper and just as durable. Straight 14s or 15s are fine.

Focus on the TIRES. The tire volume, especially with your 195lbs. AND that loaded bike, will do more for wheel longevity than anything else. When you wear out the 25s, throw on the Paselas. For you, a 26-28mm tire will be ideal, even with loads up to 15lbs. And don't forget to experiment with tire pressure. There's usually never a need to pump the tires up to maximum pressure. You'll enjoy some of the benefits of shock absorption with a tire at 80-90psi. without the harsh ride and no increased rolling resistance. But you must find out what works for you without inducing an unwanted number of pinch flats from too soft a tire.

[harlond]

http://forums.thepaceline.net/showthread.php?t=14357&page=1&pp=15&highlight=swiss

More info, some of it alluded to here, indicating butted is more durable.

[Ozz]

Don't bother spending the money on special wheels.....
Where's the fun in that?? :p

:beer:

[Vancouverdave]

What Sheldon said! Add to that, the left side of current 8/9/10 rear wheels carry so little tension that butted spokes are noticeably better at equalizing tension around the left side of a rear wheel. A rear wheel with butted spokes on at least the left side should hold up longer with less touch-up truing. YMMV.

[xtrsmith]

butted spokes will smooth out your ride.