Whats wrong? Wheel build n00b

Hi, guys.

I had a MXUS xf40 30h motor with a 28" chinese wheel, and figured I would put it to use an try to learn how to build up a wheel on the way. So I ordered a 24" crystalyte rim and some spokes. I have attached the calculator screenshot and a picture of the wheel. I used 135mm 13/14 ga Sapim spokes.

The spot where the spokes meet the nipples does not look good in my eyes. The nipples will not align correctly, and I guess they will break quite soon if I run it like this? I have tightened them to the point they "feel" like my other prebuilt wheels I have on my other bikes, but it does not look right.

Will this be better when I start using the bike, or disaster?
Should I have used a zero cross pattern?
Something else?

Looks to me like the spoke eyelets don't let your spokes align with the spoke nipples. Are those 14 guage spokes?

It may be a function of the rim you chose, or lacing pattern.

I have seen where some people file the eyelets to allow for better alignment.

As for your build, I doubt it will break apart.

PM Chalo and ask him politely if he has an opinion. He is incredible with this kind of question. Ask to have the answer posted here.
https://endless-sphere.com/forums/memberlist.php?mode=viewprofile&u=11537

The holes in the rim you have are too tightly fitted to allow the nipples to come in line with the spokes. You can fix this in one of a couple of ways. Unfortunately, you will have to unlace the wheel.

One way is to take a pencil and mark the direction each spoke leaves the rim (which direction it tilts). Then get a drill bit the size of the holes, put it in a drill, and use it to tilt the holes. Put the drill through the hole and then lean it over slowly while it's spinning. In this way you will trim the corners of the rim hole that are restricting the nipples' angle.

Another way is to drill all the rim holes about 1mm larger than they are now, and rebuild the wheel with a conical nipple washer under each nipple head.



I hope you didn't pay very much to get that Crystalyte rim, because the rims they use are quite cheaply made and crude. Now that you have it though, it's probably worth using anyway.

Oh, well. That sucked a bit, but thanks a lot for the answers! I will trim the holes like Chalo suggested. On the bright side I will have twice the experience in wheel building when I am finished.

I dont think I have the patience to do it before I go for a test-ride, though.... Too curious on how these large dd hub motor rides. Hopefully it will not be instant spoke disaster.

Should be fine for a test ride, depending on your weight.

While far from the best solution, I'd be real tempted to unlace each spoke one at at time, and put a slight bend in each spoke about a quarter inch above where the threads start. Not a huge bend, just about 10 degrees. You did start out with a good spoke.

You can try this with just one spoke, see if it works. Even if you run the spoke washers, you can just do two spokes at a time, with the wheel on the bike.

I would not do this for a pedicab, or a person that weighs more than 250 pounds, or for seriously hard single track riding where you ride down the rock staircase at 30 mph.

dogman dan said:

While far from the best solution, I'd be real tempted to unlace each spoke one at at time, and put a slight bend in each spoke about a quarter inch above where the threads start. Not a huge bend, just about 10 degrees. You did start out with a good spoke.

Click to expand...

Old thread, but:

Years ago Justin_LE thought this would be a way to make a non-radial lacing for my old CrazyBike2's rear wheel, so he sent me some to experiment with along with an order I was making for the regular spokes, but the spokes bent like this cannot be tensioned correctly, so they broke. The straight spokes radially-laced kept working.

by amberwolf » Jan 22 2023 6:29pm

dogman dan wrote: ↑Jun 11 2021 4:45am

While far from the best solution, I'd be real tempted to unlace each spoke one at at time, and put a slight bend in each spoke about a quarter inch above where the threads start. Not a huge bend, just about 10 degrees. You did start out with a good spoke.

Click to expand...

Old thread, but:

Years ago Justin_LE thought this would be a way to make a non-radial lacing for my old CrazyBike2's rear wheel, so he sent me some to experiment with along with an order I was making for the regular spokes, but the spokes bent like this cannot be tensioned correctly, so they broke. The straight spokes radially-laced kept working.

Click to expand...

You are talking about putting the bend in the spoke to work on it 1-2 spokes at a time or the single cross pattern with drilled out holes? in a small rim big DD.

ZeroEm said:

You are talking about putting the bend in the spoke to work on it 1-2 spokes at a time or the single cross pattern with drilled out holes? in a small rim big DD.

Click to expand...

Just about the part of the post I quoted in what you replied to.

Here's the original post, and a pic of the lacing
https://endless-sphere.com/forums/viewtopic.php?f=2&t=12500&p=752897&#p763615
https://endless-sphere.com/forums/download/file.php?id=114488

https://endless-sphere.com/forums/download/file.php?id=114698



This is a post discussing my conclusions at the time of the first breakages of the bent spokes
https://endless-sphere.com/forums/viewtopic.php?f=2&t=12500&#p800675
and this one has pics of the broken spokes
https://endless-sphere.com/forums/viewtopic.php?f=2&t=12500&#p801890
but I don't think they are correct, now that I know much more about building the wheels.

The problem with a bent spoke is that it isn't going to tension along it's length the same way a straight one will. The bend, because it is extra length in the spoke, means that any forces that come along to pull hard enough on it will unbend the bend, at least momentarily if not permanently deforming it, and that will release tension in the spoke and allow flexing, which over time will fatigue some part of it.

Most likely this will happen once per rotation every rotation that there is sufficient load on the wheel, but it may only happen during shock loads. The exact nature of the problem is speculation based on assumption on my part, which isn't a safe way to do things--but since we're assuming a failure, rather than a success, it's safer than the other way around.


Anyhow, you can try this type of lacing out if you like, just beware of the potential for the problem above.

Would try angling the nipple holes with a drill first. The benefit of the bend would be moving the bend away from the threads where it likes to bend, which maybe weaker. That would depend if it's butted. That is a guess on my part.
Just trying to learn as much as possible. My leafmotor in a 26" wheel has bending close to the nipple. Will try to do better on the next one the will be in a 24" so it will be not as forgiving.

ZeroEm said:

Would try angling the nipple holes with a drill first. The benefit of the bend would be moving the bend away from the threads where it likes to bend, which maybe weaker. That would depend if it's butted. That is a guess on my part.

Click to expand...

Well, I suspect any bend, regardless of location, will be problematic.

The difference in bending at the threads or thread/nonthread interface, vs only on unthreaded area, is that the threads have stress risers built into them by the nature of the change in shape, etc, within the threaded area. Any area with a stress riser (the reason for it's name) has higher stress on it vs the surrounding areas, and is more prone to cyclic-stress fractures and failure.

But because the spoke works by remaining within a specific amount of tension, anything (like a bend) that allows tension to change outside that range will allow the spoke to not work as designed, and that usually means spoke failure (if not of that spoke, of others that it is allowing tension to also change on). If the bend does not allow this to happen, it won't cause the failure, but I expect that any such bend would do so (would need to be tested for each specific design/wheelbuild, or at least computer-modelled, to verify this).

In my case, they failed at the bend itself, just like when the bend is at the threads. Since I've never tried lacing a wheel that way again, I don't have any further test data, but most likely the same problem causes it: the bend is relaxed and retensioned on every rotation of the wheel during changing loads, instead of the entire spoke, so all the forces are placed on just the bend, causing failure there. If this unloading-reloading of tension were done on the entire spoke as designed, it probably wouldn't fail (it wouldn't have a single point to fail at, anyway).

IIRC, wheels using straight spokes (no J-bends, or elbows) were designed to eliminate *that* potential failure point (which shouldn't be a problem in a properly-built wheel, but it *is* where spokes almost always break when they finally do). When I first saw a hubmotor (TC, Crown, IIRC) made this way I had never seen the original wheels like that, and didn't understand nearly as well how spokes worked, so my only reaction was "but how do we get new spokes when the original (crappy OEM) ones break?", not realizing that they also are a standard (if less common) kind of spoke.

First google hit: https://www.ptcycles.co.uk/j-bend-vs-straight-pull-whats-the-difference/ in case you've never seen straight-pull spokes and hubs.

With the hub motor so close in diameter to the rim diameter, I would definitely place that wheel radially. I've had no problems at all with wheels like that when they're laced radially. Spoke windup is negligible when the inner ends of the spokes are at such a large radius.

by Chalo » Jan 23 2023 3:45pm

With the hub motor so close in diameter to the rim diameter, I would definitely place that wheel radially. I've had no problems at all with wheels like that when they're laced radially. Spoke windup is negligible when the inner ends of the spokes are at such a large radius.

Click to expand...

So what would be a good rule of thumb, if the nipples would be angled pasted 70 degs and would bend the spokes. This would be when to lace a radial wheel?

While we have your attention Chalo, have you worked with straight spokes, are they rare? Have never seen them myself but that is not saying much.

ZeroEm said:

by Chalo » Jan 23 2023 3:45pm

With the hub motor so close in diameter to the rim diameter, I would definitely place that wheel radially. I've had no problems at all with wheels like that when they're laced radially. Spoke windup is negligible when the inner ends of the spokes are at such a large radius.

Click to expand...

So what would be a good rule of thumb, if the nipples would be angled pasted 70 degs and would bend the spokes. This would be when to lace a radial wheel?

While we have your attention Chalo, have you worked with straight spokes, are they rare? Have never seen them myself but that is not saying much.

Click to expand...

Since I have the same issue with a 24" rim, I'm reconsidering your suggestion on paired spoke holes. I was hesitating because I thought calculating the spoke lengths would be difficult, but was happy find out that the Grin spoke calculator supports paired holes. I guess my Chalo question would be how much stronger the wheel would be a radial pattern with paired holes vs normal spacing?

by E-HP » Jan 23 2023 7:53pm

ZeroEm wrote: ↑Jan 23 2023 6:27pm

by Chalo » Jan 23 2023 3:45pm

With the hub motor so close in diameter to the rim diameter, I would definitely place that wheel radially. I've had no problems at all with wheels like that when they're laced radially. Spoke windup is negligible when the inner ends of the spokes are at such a large radius.

Click to expand...

So what would be a good rule of thumb, if the nipples would be angled pasted 70 degs and would bend the spokes. This would be when to lace a radial wheel?

While we have your attention Chalo, have you worked with straight spokes, are they rare? Have never seen them myself but that is not saying much.

Click to expand...

Since I have the same issue with a 24" rim, I'm reconsidering your suggestion on paired spoke holes. I was hesitating because I thought calculating the spoke lengths would be difficult, but was happy find out that the Grin spoke calculator supports paired holes. I guess my Chalo question would be how much stronger the wheel would be a radial pattern with paired holes vs normal spacing?

Click to expand...

I'm rethinking doing a 1 cross in my up coming 24" wheel build and just go with paired spokes. Maybe I will learn something. That means drilling my motor with more holes. That will make it lighter, maybe a gram.

E-HP said:

So what would be a good rule of thumb, if the nipples would be angled pasted 70 degs and would bend the spokes. This would be when to lace a radial wheel?

Click to expand...

While we have your attention Chalo, have you worked with straight spokes, are they rare? Have never seen them myself but that is not saying much.

Click to expand...

Straight spokes have the advantage of no elbow to break from internal stresses. They have the disadvantage of minimal torque retention (so you have to hold them with a specialized tool), spotty retail support, and dedicated hubs that can only be laced in a single pattern. I'm not confident that the benefits are ever worth the drawbacks for anybody. Yes, poorly built traditional wheels break spokes. But well built traditional wheels don't, and they're much more versatile and easy to support with spare parts.

I guess my Chalo question would be how much stronger the wheel would be a radial pattern with paired holes vs normal spacing?

Click to expand...

Well I'm a convert for radial spokes in small wheels with big hubs. And I'm convinced that cross-one is the right choice for hub motor wheels where the spokes can enter the rim in line with the nipples. But there's no doubt that paired spoke radial (where either the rim or hub is paired, but not both) offers both torsional bracing and forgiving insertion angle [strike]up[/strike] to the rim. If you're willing and able to drill the hub or mix spoke hole patterns between hub and rim, there's no good reason not to try it.

Think that covers it. Drill you motor once correctly. Then you can use most rims big or small with out spending all that time modifying it to get the nipple to exit with out bending the spokes. E-hp this might be a good addition to your DIY Newb FAQ?
Thx Chalo!

ZeroEm said:

Think that covers it. Drill you motor once correctly. Then you can use most rims big or small with out spending all that time modifying it to get the nipple to exit with out bending the spokes. E-hp this might be a good addition to your DIY Newb FAQ?
Thx Chalo!

Click to expand...

Good idea. I'll try to summarize and add it to the wheel building part of the DIY Component Builder section. :thumb: If the OP is good with it, I can add his pic too.