2x Disc Wheel Build?

woolwich

Folks,

I have just laced up an Alfine Hub to a 650b Rim (standard low profile box section) using 3 crosses. I have the dishing about right and am bringing it up to tension but have a concern.

Due to the very large hub diameter and slightly smaller than average rim, the angle of the spokes on the non drive side means there is a marked kink/curve in the spokes. My gut feeling is to relace the wheel and use 2x to give the spokes a gentler time. However I have never used 2x on a disc brake wheel before and wonder if I'm chancing my luck stength wise?
Any thoughts appreciated. Relace or risk repeated spoke failure?

Cheers

cycleclinic

2x is the normal with afine hb on 26" wheels. A 650b wheel is not mch bigger. Its good you noticed as you would have spoke failure in due course. Given the hub flange is so large 2x is more optimal anyway.

woolwich

Thank you. It does look like it will fail sooner rather than later. I'll relace it and try again.

ugo.santalucia

If you relace, you need shorter spokes... there is about 3-4 mm difference between a 2 and a 3 cross, which is too much for the same spoke length
I have a 36 spokes wheelset at 4 crosses where the spoke nearly overlaps with the next spoke head... it has not given any problem for about 30 years.

If you build your own wheels, it is no big deal, you can try it as a 3 crosses and if a spoke breaks, you just rebuild it as a two cross... seems a shame to waste your spokes

woolwich

Ugo,

Thanks for the ballpark 3-4mm figure. Useful to know, I hadnt realised it would be quite so much.

The angle Iam particularly worried about is the angle at the nipple end, which has quite a marked kink where the spoke enters the nipple. The hub end is tidy, almost a tangent and everything laying nice against the flange.


I would have been inclined to agree with you and just try it see how it works out. However the wheels are for a custom frame for my rather small Mrs and I want to trust they will be reliable, she isnt particularly mechanically gifted at the roadside.
As it happens, due to availability, I was forced to round the spoke lengths when I ordered. Therefore I have a little spare thread showing on the non drive side( problem side) and might just get away with going 2x length wise. The other side are perfect length and appear just good.

So without additional cost would it be possible to slacken everything off, leave the good side in place 3x and just relace the problem side 2x? Is this feasable? Would it look appalling?

Cheers for your thoughts

ugo.santalucia

woolwich wrote:

Ugo,

Thanks for the ballpark 3-4mm figure. Useful to know, I hadnt realised it would be quite so much.

The angle Iam particularly worried about is the angle at the nipple end, which has quite a marked kink where the spoke enters the nipple. The hub end is tidy, almost a tangent and everything laying nice against the flange.


I would have been inclined to agree with you and just try it see how it works out. However the wheels are for a custom frame for my rather small Mrs and I want to trust they will be reliable, she isnt particularly mechanically gifted at the roadside.
As it happens, due to availability, I was forced to round the spoke lengths when I ordered. Therefore I have a little spare thread showing on the non drive side( problem side) and might just get away with going 2x length wise. The other side are perfect length and appear just good.

So without additional cost would it be possible to slacken everything off, leave the good side in place 3x and just relace the problem side 2x? Is this feasable? Would it look appalling?

Cheers for your thoughts

It is possible, yes and yes often mixed laced wheels do look appalling, but as long as they are effective....
Next time you need spokes, let me know, I can address you to places where you can get any length at reasonable prices

woolwich

Thanks again for your help folks. For peace of mind I will relace the problem side. If I really cant stand the looks I'll do the other side and be in touch for spokes. I'll just put the cost down to experience. In future I'll do all hub geared bikes 2x.

Cheers

cycleclinic

I carry most lengths so long as they Sapim.