Pulling spokes laced elbows in or out?

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alcatraz
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by alcatraz

Hi wws

I'm wondering what would be the better choice? Should the pulling spokes be laced elbows in or out?

The difference being how the wheel acts under torsional load. Does it benefit from a shallower or steeper bracing angle under torsional loads?

It's a 2:1 build 0x:3x if that is of any interest.

Thanks /a

bm0p700f
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by bm0p700f

Your overthinking things. torque transmission means minimising tension changes in the spokes from a given pedalling torque. Interlacing sorts out the bracing angle. Mine

Think about it the pedalling torque causes tension changes in all the spokes. In a 24 spoke wheel laced 2x, 6 spokes Ds and 6nds see a tension increase (pulling spokes) and the other 6 see a tension reduction (trailing). Given the load is distribute amongst all 24spokes I don't think it's right to say only the pulling spokes transmit torque they all do. They all experience tension changes. It is that tension chnage that transmit motive force.

My pulling spokes are heads in and trailing spokes are head out. They both transmit torque.

by Weenie


alcatraz
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by alcatraz

I would instinctively lace pulling spokes heads in too. Feels right for performance (however marginal the difference might be).

Sure it will stress the elbow joints more as those spokes will see forces of >120 and have to go over the flange edge as well, while the trailing spokes will see forces of <120.

I would imagine that as torsional load is applied the position of the crosses move outward if laced like this (trailing spokes give way to the pulling spokes tensioning). The opposite should be true if pulling spokes are laced heads out and later crossed over/under.

If spoke failure would be my main concern I'd maybe do the opposite so that the spokes with less tension have the problem of bending over the flange edge like a fulcrum, how to say. You know what I mean.

Comparing straightpull hub designs, Extralite sits on one side with all hubs having pulling spokes closer to hub center. Dtswiss and Carbonti have the pulling spokes away from center (on the ds side). Just an observation. I'm not trying to read too much into it.

Marin
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by Marin

On road wheels with small cassettes, pulling spokes heads out so that when tension increases, the 2nd crossing is not pulled towards the derailleur cage but away from it. On some builds, this made a big difference for my Red derailleurs.

alcatraz
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by alcatraz

Good point!

bm0p700f
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by bm0p700f

Pulling spokes heads in should increase rd cage clearance.

Never had an issue with rs vlearance even with 21t final sprockets on 11 speed.

alcatraz
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by alcatraz

How would they increase rd cage clearance?

Isn't the opposite true?

mr4fox
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by mr4fox

In my head when torque is applied via the chain/cassette the hub will want to move inboard since you’re lacing 2:1 and only have pulling spokes on the drive side. So makes sense to me to lace pulling spokes heads out to minimize the bracing angle of those spokes to minimize the laterally pull on the hub (relative to the rim)

TheKaiser
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by TheKaiser

bm0p700f wrote:
Wed Apr 17, 2019 10:38 pm
Pulling spokes heads in should increase rd cage clearance.

Never had an issue with rs vlearance even with 21t final sprockets on 11 speed.
Yeah, that's backwards, no?

bm0p700f
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by bm0p700f

I lace my wheels the gerd schraner way. The point being that is supposed to increase rd clearance. In fact you can do it the other way and it make no odds.

When pedalling the hub/spokes should be pulled away from the rd so have the pulling spoke laced heads in means it is interlaced and therefore bent away from the rd and therefore you get more rd clearance when the wheel flexes under torque. However this is marginal at best to a pointless reason.

Disc brakes means you now have pulling and pushing spokes both doing the same thing. Therefore for a disc brake bike it really makes no difference which way you lace for rd clearance.

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Last edited by bm0p700f on Tue Apr 23, 2019 6:52 am, edited 1 time in total.

NickJHP
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by NickJHP

I've never bothered about which spokes are heads out or heads in. And with disc wheels, all the spokes are pulling spokes. Half of them when you're stomping on the pedals, and the other half when you're braking.

bm0p700f
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by bm0p700f

Your right not to be bothered nick hense my last post.

TheKaiser
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by TheKaiser

bm0p700f wrote:
Mon Apr 22, 2019 9:36 pm
I lace my wheels the gerd schraner way. The point being that is supposed to increase rd clearance. In fact you can do it the other way and it make no odds.

When pedalling the hub/spokes should be pulled away from the rd so have the pulling spoke laced heads in means it is interlaced and therefore bent away from the rd and therefore you get more rd clearance when the wheel flexes under torque. However this is marginal at best to a pointless reason.
I still don't quite get how Schraner's way will increase derailleur clearance vs the Jobst Brand suggestions, however I concede that it is a little murky, particularly when you add the changes in dish when under drive torque, and either way, is probably a trivial concern for all but the closest clearance bike setups.

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Calnago
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by Calnago

Schraner’s method has nothing to do with the resulting derailleur/spoke clearance. I use it too but it’s the lacing pattern and where and how the interlace happens that sometimes “might” get a little close to the derailleur cage surrounding the upper pulley. You can lace the drive side pulling spokes heads in or heads out regardless of the method you use to lace the wheel. In a 3 cross 32 hole scenario for example, drive side pulling spokes heads out will result in the pulling spoke final cross on the outside of the crossing spoke, so that in a severe torque situation the tension would pull things towards the center of the hub rather than push them out toward the derailleur. The other factors to consider for derailleur/spoke clearance are rim profile and flange width, both of which are factors in play as far as how close the spokes end up to the derailleur. Round spoke cross sections crossing over each other will also end up leaving less clearance than flat spoke cross sections would. But as TheKaiser mentioned, probably few scenarios these days have spoke/derailleur clearance issues, especially with high profile rims, and the ever increasing size of the largest rear cog.
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bm0p700f
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by bm0p700f

As I have said it a moot point anyway. Derailleur clearance is not an issue that needs to worried about. As lacing barely affects it. The days of corn cob cassettes are gone.

by Weenie


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