Wheel building question

[dekindy]

What's up?

I rode my new built up rear wheel a little over 200 miles. When I investigated a squeaking noise that my bike was making I discovered a couple of nds spokes that were obviously loose and others with reduced tension. My wheelbuilder said that all the spokes, nds & ds, had loosened one full turn. He retensioned the wheel and told me to ride it 150 miles and bring it again to verify it is okay.

Details - White Industries 28-spoke hub mated to a Velocity Deep V rim using DT Swiss Spokes and brass nipples all the way around.

BTW - Everybody on the training ride when the noise started guessed everything but my wheels as the source.

[gdw]

how much do you weigh? How experienced is your wheelbuilder?

[dekindy]

how much do you weigh?
How experienced is your wheelbuilder?


205 lbs

I thought very experienced. Not so sure now.

[gdw]

Did he use Revolutions?

[dekindy]

14/15 double butted is all the detail I have. Spokes are not an item I have a lot of knowledge about. I let him decide on spokes and nipples. I know I had bladed on the front and he did not have stock spokes that would match and I did not want to wait. They look identical to the untrained observer.

[gdw]

1 Spokes can wind-up as a wheel is brought to tension and then unwind, loosen, when used. Light spokes like Revolutions are more prone to wind-up than heavier models although it can occur with standard butted spokes.
2 I believe that Velocity Deep V's are built without eyelets. The nipples might be bedding into the rim as you ride. As they mate with the rim they loose tension.

I wouldn'y worry about the tension issues unless problems occur shortly after the next visit. If the spokes loose tension after the second visit, you need to find a new builder.

[dekindy]

Thanks, gdw.

[Peter P.]

A properly built wheel should NOT require a retensioning after ANY break in period. If they do, then the builder doesn't know what they're doing. After 30 years of building wheels, that's my experience.

Something odd is going on. Are the nipples alloy? Were 14 ga. nipples used with 15 ga. spokes?

[dekindy]

A properly built wheel should NOT require a retensioning after ANY break in period. If they do, then the builder doesn't know what they're doing. After 30 years of building wheels, that's my experience.

Something odd is going on. Are the nipples alloy? Were 14 ga. nipples used with 15 ga. spokes?

I have gotten several replies on another forum that agree with you. I am hoping he got it right the second time. If it does not stay tensioned this time I will take it to another builder and pay them to have it rebuilt.

[dvancleve]

As others have opined, this is an easy build. The super butted 14/17g type spokes take some extra effort and still sometimes wind up but standard 14/15g should be pretty solid after a decent build. I would guess your builder is pretty new and didn't pre-stress the wheels or didn't account for the spokes twisting. If you think about the nature of a wheel, the nipples can't really move in the rims, so the loss of tension is the spokes unwinding and effectively getting longer as you put stress on them by riding. Something you can do when you bring them home again is get some leather gloves and go around both sides of the wheel squeezing the pairs together as hard as you can. If you hear any pinging or it goes out of true again, he still didn't get it. FWIW I have done about 50 wheels...

Best wishes, Doug

14/15 double butted is all the detail I have. Spokes are not an item I have a lot of knowledge about. I let him decide on spokes and nipples. I know I had bladed on the front and he did not have stock spokes that would match and I did not want to wait. They look identical to the untrained observer.

[soulspinner]

No expert, but why at 205 pounds bother with 28 spokes, why not just concede a few grams and build a 32 rear to cope with your weight and power?

[dekindy]

No expert, but why at 205 pounds bother with 28 spokes, why not just concede a few grams and build a 32 rear to cope with your weight and power?

Valid point.

I bought the wheels used for half price but consulted the original builder to verify they would hold up under my weight. If White Industries had not warranted the hub I was going to go replace the 28 hub with a 32. Weight would be the only consideration since I am not a powerful rider. I did replace the original Aerohead O/C with the Deep V rim for extra strength. I verified from several sources that a Deep V with 28 spokes is sufficient.

[dekindy]

As others have opined, this is an easy build. The super butted 14/17g type spokes take some extra effort and still sometimes wind up but standard 14/15g should be pretty solid after a decent build. I would guess your builder is pretty new and didn't pre-stress the wheels or didn't account for the spokes twisting. If you think about the nature of a wheel, the nipples can't really move in the rims, so the loss of tension is the spokes unwinding and effectively getting longer as you put stress on them by riding. Something you can do when you bring them home again is get some leather gloves and go around both sides of the wheel squeezing the pairs together as hard as you can. If you hear any pinging or it goes out of true again, he still didn't get it. FWIW I have done about 50 wheels...

Best wishes, Doug

I have ridden the wheel 90 miles since the retensioning. Should I still do this?

[mister]

28spokes on a deepv should probably be ok with your weight. they aren't the lightest rims.
i have some 28hole ambrosio's that are holding up fine and i'm definately over 205lbs with clothes and lock and other various items in my bag.

i haven't had to retension a wheel ever.

[rmsmith]

The drive side spokes should be a straight gauge, and the non-drive side should be the double or triple butted variety. You can look-up your rear hub's flange dimensions, which are typically measured as offset from the center. The issue is a simple engineering statics problem: 0 = Tension(ds) - Tension(nds). I looked up the numbers for my DT Swiss hubs, and discovered that the drive side spokes need 1.96 times the tension as the non-drive side spokes to maintain equilibrium in the rim's position.

[weiwentg]

The drive side spokes should be a straight gauge.

why?

[rmsmith]

why?

When a spoke is tightened it will stretch a certain amount like a spring, and as the loaded wheel rotates the tension will increase and decrease, but there should always be tension in the spoke during rotation. The hubs dimensions are given as flange offset from the center line, which is where the rim aligned. Since the flanges on the rear hub are not equidistant the spokes on the flange nearest the center line must exert a greater tension to hold the rim aligned on the center line. If the spokes on the drive side are the same as the non-drive side, the spokes on the drive side will be stretched more than the non-drive side. It's the non-drive side spokes that tend to loosen first because they are not stretched enough to begin with. In order to have adequate stretch in both spokes the drive side spokes need to have a larger cross-sectional area, i.e., a thicker spoke.

A "lay-person" example: Take a twenty foot long tent pole with two ropes fastened at the top. A tug of war ensues between two people of equal strength with each pulling on their rope. However, one person must stand five feet from the base of the vertical pole while the other person gets to stand fifteen feet from the pole. Knowing that they both have the same strength who would you bet on to win the contest?

[dekindy]

There seems to be a wide diversity of opinions about spoke selection. Response to my question on other forums have indicated that using butted spokes all around is preferable to straight gauge.

I guess it is going to come down to whether the wheel holds up and the spokes retain tension. They either will or they won't. If they don't, I guess I will have to figure out Plan B myself since everyone seems to have a different opinion. I can't figure out who really knows what they are talkng about.

[Birddog]

I can't figure out who really knows what they are talkng about.

Did you pose this question over on the Salon?

Birddog

[dekindy]

Did you pose this question over on the Salon?

Birddog

What is the Salon? I just posted the question on Roadbikerider.com, of which I am a member and respect their expertise, and have not received a response yet.

[rmsmith]

There seems to be a wide diversity of opinions about spoke selection. Response to my question on other forums have indicated that using butted spokes all around is preferable to straight gauge.

I guess it is going to come down to whether the wheel holds up and the spokes retain tension. They either will or they won't. If they don't, I guess I will have to figure out Plan B myself since everyone seems to have a different opinion. I can't figure out who really knows what they are talkng about.

You are correct about the butted spokes being better. I probably should have said that any spoke, butted or straight gauge, with a larger cross-sectional area should be used on the drive side.

I have a set of light-weight DT Swiss 240/R-1.1 wheels, and they have the Revolution triple butted spokes that are 1.5-mm at their mid-section, and the drive side uses Super Competition triple butted spokes that are 1.8-mm at their mid-section. They have been a very successful build with over 4,500-miles now.

[rmsmith]

There seems to be a wide diversity of opinions about spoke selection. Response to my question on other forums have indicated that using butted spokes all around is preferable to straight gauge.

I guess it is going to come down to whether the wheel holds up and the spokes retain tension. They either will or they won't. If they don't, I guess I will have to figure out Plan B myself since everyone seems to have a different opinion. I can't figure out who really knows what they are talkng about.

OK, I finally got around to doing a simple statics free-body diagram in Microsoft Word, and converted it to an Adobe PDF file, and here it is attached.

[weiwentg]

When a spoke is tightened it will stretch a certain amount like a spring, and as the loaded wheel rotates the tension will increase and decrease, but there should always be tension in the spoke during rotation. The hubs dimensions are given as flange offset from the center line, which is where the rim aligned. Since the flanges on the rear hub are not equidistant the spokes on the flange nearest the center line must exert a greater tension to hold the rim aligned on the center line. If the spokes on the drive side are the same as the non-drive side, the spokes on the drive side will be stretched more than the non-drive side. It's the non-drive side spokes that tend to loosen first because they are not stretched enough to begin with. In order to have adequate stretch in both spokes the drive side spokes need to have a larger cross-sectional area, i.e., a thicker spoke.

A "lay-person" example: Take a twenty foot long tent pole with two ropes fastened at the top. A tug of war ensues between two people of equal strength with each pulling on their rope. However, one person must stand five feet from the base of the vertical pole while the other person gets to stand fifteen feet from the pole. Knowing that they both have the same strength who would you bet on to win the contest?

honestly, the second part made little sense to me. as to the first part, butted spokes are more durable than straight gauge. so, one can use a thinner gauge spoke on the NDS. but it makes no sense that the DS spoke must be straight gauge.

[rmsmith]

honestly, the second part made little sense to me. as to the first part, butted spokes are more durable than straight gauge. so, one can use a thinner gauge spoke on the NDS. but it makes no sense that the DS spoke must be straight gauge.

So if the non-drive side uses a 2.0/1.8 butted spoke, and the only larger diameter spoke offered is a straight gauge why not use them on the drive side? DT Swiss still manufactures them, so they must still be functional as a spoke. I use a 3x pattern for durability too.

BTW, as I mentioned in earlier, I do agree with you that a butted spoke is a better choice, but I didn't have that choice in seeking a larger diameter. I did look closely at the Alpine III spokes, but settled on the straight gauge because the Alpine III spoke needed a larger hole in the flange.

[dekindy]

I went searching on roadbikereview.com's wheels and tires forum and the first thread that came up was rmsmith's question about spoke guages. The responses indicate that the same spoke can be used on the ds and nds if I am understanding the replies correctly. Here is the url:

http://forums.roadbikereview.com/showthread.php?t=136547&highlight=spoke

[ergott]

The individual component choice isn't the issue here. If those wheels aren't holding together, it's a build issue. In this situation, there is nothing wrong with 2.0/1.8/2.0mm spokes on both sides. The advantage of dissimilar spokes is most with 2.0/.1.5/2.0mm spoke on the NDS and 2.0/1.8/2.0mm spokes on the DS.

Spoke twist is hard to blame here as even if not payed attention to, 2.0/1.8/2.0mm spokes do not have that much spoke windup to loosen a wheel up that much. Sound like a combination of incorrect tension to begin with, a lack of cold working of the spokes during the build, and no stress relieving. I can't say without the wheel in front of me.

Let us know how the wheel holds up after this second working.

[dekindy]

The individual component choice isn't the issue here. If those wheels aren't holding together, it's a build issue. In this situation, there is nothing wrong with 2.0/1.8/2.0mm spokes on both sides. The advantage of dissimilar spokes is most with 2.0/.1.5/2.0mm spoke on the NDS and 2.0/1.8/2.0mm spokes on the DS.

Spoke twist is hard to blame here as even if not payed attention to, 2.0/1.8/2.0mm spokes do not have that much spoke windup to loosen a wheel up that much. Sound like a combination of incorrect tension to begin with, a lack of cold working of the spokes during the build, and no stress relieving. I can't say without the wheel in front of me.

Let us know how the wheel holds up after this second working.

It will be a week or two. My Legend frame dropout developed a crack so I will not be riding the wheels until it is fixed.

The wheels had the 150 recommended miles when I took in the bike for repair. Tension appeared to be holding but I am not an expert. Hopefully the build has been corrected because I will probably only have a couple of days to test the bike before the 160-mile RAIN ride. I will obviously not be happy if the wheel fails on this ride because I do not have a SAG or spare wheel right now.

[rmsmith]

Here's an earlier thread addressing the same issue:

http://forums.thepaceline.net/showthread.php?t=9304

My intention was to introduce some engineering mathematics, i.e., statics into the discussion to describe the disparity in tensile forces between the two sides. I like the offset rim idea, but I wanted the DT Swiss TK 7.1 rim because of its sturdy design.