I dont know what length they use. I use 12mm on all three sets on my 742 built.

 

Thanks ckspeed! I guess a 12mm nipple extends far enough through the rim to get a wrench on it. What nipple wrench do you use? I use a Spokey for DT Swiss 12mm brass nipples.

Do I dare ask? Did you use aluminum or brass nipples for your builds? I'm planning on using nipple washers(Ibis directed me to these: Sapim HM Internal Stainless Steel Cupped Nipple Washer) and brass nipples, although I'd like to use some splined aluminum nipples I have, but I'm worried about galvanic/other corrosion.

 

Brass nipples and park tool nipple wrench and other brand, don’t remember. I did not use nip washer. If you use the washer, I think it’s best to go with 14 mm nipple length.

 

14mm or even Wheelsmith/Sapim 16mm work well for carbon rims.

Using 16mm vs 12mm DT Swiss nipples will change your spoke length, not the same for Sapim & Wheelsmith.

 

I asked the same thing and this is what Chuck said:

Head over to our wheels page:
https://www.ibiscycles.com/wheels/

Click on the setup tab. You'll see the spoke lengths there.

We use these nipples:
Sapim Double Square Alloy Nipples (Black), 14g/16mm

 

Thanks for all the responses!

If you use the washer, I think it's best to go with 14 mm nipple length.

Thanks for that, ckspeed! I've got the washers in hand.

We use these nipples:
Sapim Double Square Alloy Nipples (Black), 14g/16mm

Wow! Ibis uses alloy nipples? I wonder if that is the primary reason they use nipple washers?

Ibis emailed me this response:

We use a 16mm nipple in our Industry Nine/Ibis Rim builds, and a 14mm nipple in our Ibis Logo Wheel/Ibis Rim builds.

1) I'm not sure why different hubs would necessitate a different nipple length.

2) It doesn't make a whole lot of sense to me why they would use 16mm nipples when it's possible to build with 12mm nipples--although because ckspeed didn't use nipple washers, 14mm nipples seem like they should work with nipple washers.

And per Roger Musson, for DT Swiss 14mm nipples subtract 1mm from the spoke length, and for DT Swiss 16mm nipples subtract 2mm from the spoke length.

 

I ended up building my rear 742 wheel with high strength 14mm aluminum nipples from wheelbuilingparts.com

Unfortunately, 3 months later I'm experiencing this:

The spoke is fine, it's the nipple that cracked.

I used one wrap of Kapton tape, and the tape held up fine, there was no leaking sealant. This is the second drive side spoke that malfunctioned in the past two weeks.

 

If the spoke didn't break then they look like they are too short. You may want to try longer D-light spokes, there's no fear of bottoming out with D-Lights since the taper starts right at the thread end. You could go al the way through the spoke and past the slotted head.

I ended up building my rear 742 wheel with high strength 14mm aluminum nipples from wheelbuilingparts.com

Unfortunately, 3 months later I'm experiencing this:

View attachment 1249722

The spoke is fine, it's the nipple that cracked.

I used one wrap of Kapton tape, and the tape held up fine, there was no leaking sealant. This is the second drive side spoke that malfunctioned in the past two weeks.

 

Is there any corrosion on it or does it look like a clean fresh break? I just use brass now after dealing with stuff like this and alloy nips, I'll take the weight penatly. 3 months is pretty short though, did you use a tensiometer during the build and recheck a few good rides later? I wonder if those spokes weren't loading and unloading or something.

 

Is there any corrosion on it or does it look like a clean fresh break?

No corrosion. Clean break.

Did you use a tensiometer during the build and recheck a few good rides later?

I used a Park tensionometer while building. My Onyx rear hub has a max 120 kgf, so I built to that tension. I don't recheck tensions after a few rides because mounting a tire reduces the tension. I did recheck tensions after the first nipple broke because I had to take the tire off to dig out the broken nipple, and I had to re-tightend all the spokes to get back to 120 kgf. I do plenty of stress relief by squeezing parallel spokes when building, so I was surprised that I needed to retighten all the spokes.

In hindsight, I realize I heard the first spoke break when I sat on my bike one day. I had just finished doing some work on my bike, and when I sat on the saddle I heard a sound like carbon cracking. I thought, "Oh no! Did I tighten the seatpost clamp too tight?!!" I looked at the seat tube, and I couldn't see any cracks. Next, I went back through the steps of what I did, and I remembered lowering the torque on my torque wrench to 5 Nm. To confirm, I loosened the seatpost clamp 180 degrees, then I used my torque wrench to retighten, and I ended up going a little farther than 180 degrees back in the other direction. I searched everywhere on my bike, but I couldn't find any cracked carbon.

It wasn't until a few days later that I heard some rattling in my rear wheel. Then I squeezed all the spokes, and I found the spoke with the broken nipple. When the nipple snapped, the spoke remained in the spoke hole, so I wasn't able to detect the broken spoke by just looking at my wheel.

I have a theory. I think the stainless steel nipple washers I used (and that Ibis recommends) may have cut the nipple. After my build, I noticed that some of the drive side nipples didn't quite orientate in line with the spokes, like this:

(image from Roger Musson's ebook Professional Guide to Wheel Building: A Complete Reference for Cyclists (7th ed))

I didn't like the looks of those spokes.

 

Linked to a video showing how to do it basically, but I put it on the floor on a mat, then apply all my body weight on opposite sides of the wheel, I rotate the wheel 8 times hitting all parallel spokes.

I follow Roger Musson's wheel building book, and although he mentions that method of stressing a wheel, he says he doesn't use it--instead he squeezes parallel spokes. I'm certainly not an expert wheel builder: this was only my 7th wheel that I've built and my first carbon wheel. In any case, I never hear any pinging of spokes when I ride my new wheels for the first time, so I think they are properly stress relieved. On the other hand, my spokes did seem to loosen on my latest build.

One other thing, not certain of those rims, but some are actually directionally drilled, so if you lace it wrong, the angle the spokes come out of the rim will be worse than if it was a regular drilled rim and you will experience what you're thinking of.

Yeah, I checked the drilling very carefully. I'm pretty certain I laced the wheels correctly. There's one way to find out: can someone look at their rear 742 wheel, then look at the first spoke to the left of the valve stem and tell me which side of the hub that spoke goes to? The drive side or the non-drive side? Secondly, is the elbow of the spoke on the inside of the hub flange or the outside? Thanks.

 

If the spoke didn't break then they look like they are too short.

In that case, wouldn't the nipple crack right at the end of the spoke (or above the end of the spoke)?

 

Here's a pic from another thread on MTBR:
The nipple is weakest where the slot is. If the spoke goes though til the end, it reinforces the nipple, but for most spokes, there's not too much margin for error and you can bottom out on the threads, making it hard to reach the right tension.

It's possible your spoke extended a little past the weakest part of the nipple but not enough to fully reinforce it?

Here's another good pic:

 

My nipple cracked where the spoke was reinforcing the nipple, i.e. below the end of the spoke, not where the red arrow points to in the image, which is at the end of the spoke (or above it). See what I'm saying?

 

Yeah, I see now. What brand of nipples? They could have been defective. I've always used Sapim Al nipples and never had an issue @175lbs.

 

High strength 14mm aluminum nipples from wheelbuilingparts.com.

 

Switch to Sapim or Brass