spoke hole alternating offset; lacing

[marciero]

On a low profile rim the spokes are slightly offset to alternating sides. Both Jobst Brandt and Sheldon Brown have you lacing spokes to holes on the rim that are offset to the same side as the flange. Since the holes themselves are drilled straight through and not angled (as in deeper rims) why would you not want to lace to the opposite side in order to minimize effective dish?

[oldpotatoe]

On a low profile rim the spokes are slightly offset to alternating sides. Both Jobst Brandt and Sheldon Brown have you lacing spokes to holes on the rim that are offset to the same side as the flange. Since the holes themselves are drilled straight through and not angled (as in deeper rims) why would you not want to lace to the opposite side in order to minimize effective dish?

If the spoke holes are drilled straight, it doesn't matter how you lace, the dish will be the same. DT465/415 had holes not offset but dish remains the same.

[marciero]

If the spoke holes are drilled straight, it doesn't matter how you lace, the dish will be the same. DT465/415 had holes not offset but dish remains the same.

OP- was hoping you would chime in. To be clear, the holes are indeed offset, but not drilled at an angle; that is, they are drilled straight through the upper and lower sections of the rim. These are tb-14.

[oldpotatoe]

OP- was hoping you would chime in. To be clear, the holes are indeed offset, but not drilled at an angle; that is, they are drilled straight through the upper and lower sections of the rim. These are tb-14.

I wouldn't lace to alternate holes as it may put some strain on the spoke/nipple interface.

[marciero]

I wouldn't lace to alternate holes as it may put some strain on the spoke/nipple interface.

Was hoping you would say that!
I just built these up and had been considering re-doing the rear. I suppose the added strain would be due to the fact that the holes would be canted to one side or the other due to the slight curvature of the rim bed? This canting seems to be very subtle on the TB-14. I cant see it.

This is first time I've built an 11-sp wheel and was somewhat alarmed by the difference in tension.

[ergott]

This is first time I've built an 11-sp wheel and was somewhat alarmed by the difference in tension.

Which hubs?

[thwart]

This is first time I've built an 11-sp wheel and was somewhat alarmed by the difference in tension.
Like a lot of things (including owning a VW diesel :crap: ) things were much easier and simpler back in the old days.

5, 6 or 7 speed... less dish, easier to build.

[marciero]

Which hubs?

They are Ultegra 6800.

[fuzzalow]

In a simple structure like a bicycle wheel, yes there is no reason why you could not lace a rear wheel using the offset drilling in the rear rim to the reverse of its L/R spoke drilling. I've considered doing this also in the past and I have never attempted doing it this way but I have not been able to come up with a reason why not - other than a fear of bucking tradition and orthodoxy. Oh yeah, maybe also I wasn't comfortable with the underlying engineering that would result in doing this.

Lacing the rear wheel in the reverse of the spoke offsets in the rim will increase the bracing angle of the spokes from the hub flange to the rim. But being that both the DS and NDS spokes have been offset to the same distance by using the reverse drilling that should be a wash as far the tension imbalance between L & R spokes. What will probably increase dramatically will be the overall spoke tension in effect throughout the wheel to maintain the structural equilibrium of the wheel via a vis the DS and NDS spokes. And that is the part the bothered me.

In building modern rear wheels with the extreme dish required for 11-speed cassettes, there is almost an on the limit amount of tension run into the DS spokes as far as what an alloy rim can handle. And a carbon rim can handle less than that although Enve gets around that limitation by a different nipple design. So lacing and building a rear wheel in a reverse offset rim patten gets slightly better dish in trade-off with much higher tension required in the wheel which puts durability of the spoke/rim interface at risk. That is the reason I'd guess this is not commonly done because the solution seems so obvious on its face.

See, what oldpotatoe told you in 10 words or less took me three paragraphs. :o

[ultraman6970]

IN my 1st set of wheels I built when I was like 13 y/o... I did laced at the opposite side of the of the rim and I got all the spokes loose after like 15 minutes of riding. Never knew exactly the reason of it.

[ergott]

It doesn't change the tension imbalance since you are adding to the bracing angle on both sides. In reality the difference is typically less than 1mm so I wouldn't bother.

Yes the new Ultegra hubs have less than ideal flange spacing. I think an offset rear rim is the best solution. The DT440 mates up real well to Shimano and Campagnolo hubs.

[marciero]

Lacing the rear wheel in the reverse of the spoke offsets in the rim will increase the bracing angle of the spokes from the hub flange to the rim. But being that both the DS and NDS spokes have been offset to the same distance by using the reverse drilling that should be a wash as far the tension imbalance between L & R spokes.

Not quite a wash, since the ratio of the two offsets would get closer to one.

[marciero]

It doesn't change the tension imbalance since you are adding to the bracing angle on both sides.


This still results in ratio of bracing angles that is closer to one, so would change tension imbalance. But I hear ya-is probably negligible. That said, increased DS angle with same tension imbalance would still be desirable.

[fuzzalow]

Not quite a wash, since the ratio of the two offsets would get closer to one.

Dunno, how many angels on the head of a pin?

In practical terms at the precision necessary and in effect for a primitive structure like a bicycle wheel, I don't see any harm in calling it a "wash". No Hadron Collider math needed on this solution!

[ergott]

This still results in ratio of bracing angles that is closer to one, so would change tension imbalance. But I hear ya-is probably negligible. That said, increased DS angle with same tension imbalance would still be desirable.

Not sure we are talking about the same thing. The OP's rim is not an offset drilled rim in that all the spokes holes are off to one side. It's a simple left/right alternation that almost all eyeleted rims have. If you do the opposite lacing the left flange spokes are slightly right of center and the right flange spokes are slightly left of center. That's a wash.

[marciero]

Not sure we are talking about the same thing. The OP's rim is not an offset drilled rim in that all the spokes holes are off to one side. It's a simple left/right alternation that almost all eyeleted rims have. If you do the opposite lacing the left flange spokes are slightly right of center and the right flange spokes are slightly left of center. That's a wash.

As fuzzalow notes, in practical terms is probably a wash. But increasing two different (positive) values, in this case the flange-to-spoke hole offsets, by the same amount makes their ratio closer to one. So the tension ratio would be closer to one as a result.

[oldpotatoe]

It doesn't change the tension imbalance since you are adding to the bracing angle on both sides. In reality the difference is typically less than 1mm so I wouldn't bother.

Yes the new Ultegra hubs have less than ideal flange spacing. I think an offset rear rim is the best solution. The DT440 mates up real well to Shimano and Campagnolo hubs.

Concur as do latest gen Velocity A23.

[marciero]

I went with TB-14 mostly for aesthetics on this steel frame and fork. Is like a modern-day Open Pro (and I am a fan of Open Pro). As for the 6800 hubs- I wanted loose ball, and the quality, price, and aesthetics of these are an unbeatable combo. This newest Ultegra has the latest and greatest features of DA 9000.