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-   -   The small wheel building thread. (http://www.bikeforums.net/folding-bikes/933053-small-wheel-building-thread.html)

cpg 02-06-14 07:38 AM

The small wheel building thread.
 
Hi All. I thought it would be useful to have a thread dedicated to building small wheels where hints and tips can be given and questions answered. While there is plenty of information on the net about building wheels its often aimed at full size wheels but small wheels are different animal.

To start things off I have a question about spoke cross patterns. I am considering rebuilding a 349 Bickerton rear wheel on a SA 3 speed hub. Its currently a 2 cross pattern, could I go to a 1 cross pattern and would there be any disadvantages?

rhenning 02-06-14 08:19 AM

2 cross is stronger and the weight saving of one cross would not be much. 1 cross would also ride a bit harder. A Bickerton is such a bad riding bike I am not sure you would notice it. At least the two Bickertons I own are and I own 75+ bikes of which about 15 are folders. I have one of the originals with 14 inch and 16 inch wheels and one of the later ones with 16 inch and 20 inch wheels. They are the worst riding bikes I own by a significant margin. They go where the want to go because the frames flex so much. Not necessarily where you want them to go. From wheel builder point of view there is no difference between building a small wheel versus a big wheel except I am not sure you could do a 4 cross on a small wheel but I have never tried that yet. Roger

mark03 02-06-14 09:15 AM

I will soon be building a 406 wheel with Alfine 11 hub, and had the same question. I think all you can do is try lacing it up at the higher # of crosses and check the angle the spokes make w.r.t. the hub. I think I read that for some extreme cases (Nuvinci?), one cross makes more sense as with two cross you are already tangent to the hub. And someone in another thread cited a mfg. recommendation that all wheels with X hub be built as one cross. There seem to be plenty of anecdotes but little authoritative advice.

BTW you should add some hyphens in the subject, otherwise it may remain a small thread! :lol:

ThorUSA 02-06-14 09:30 AM

only difference to large wheels
is the angle of the spoke coming out of the rim ....
Meaning the Nipple is sitting in the hole, nice and straight... now the spoke wants to go to the corresponding hole in the hub... obviously straight laced is no problem , the more crosses you have the more angle you will see, too much angle and the spoke will never be tight enough due to the bend, and will loosen all the time. ALso the spoke will break at the nipple ...

Sapim Polyax nipple are somewaht conical shaped and they follow the spoke better than all others, why other peeps dont do that is a miracle to me.

But even Sapim nips cant overcome some weird 3 cross angles some folks still do on the smallest wheels.

Harsh riding for straight laced spokes, might be a issue for big ole wheels, and I am not sure about this as it feels to me, it could be one of those things, which just doesnt want to go away ( steel versus alloy, derailleur bike versus IGH .... and so forth ) I tend to believe that 5 lbs more or less in any given tire will make a larger input...

Straight laced spokes in the past were also a mark of a very cheep bike, as it is easier and faster to built crappy 2 dlr wheels ...

I would go straight in front, 2 cross on drive side

best Thor

cpg 02-06-14 09:32 AM

Thanks for that Roger. The first 349 wheel I built I followed conventional wheel building theory and did it 3 cross but I realise now that was over the top. Wheels this size are already inherently stiffer than 26" or 700 wheels so I could have got away with fewer crosses and still have a strong wheel.
I have agree with Thor, I had one spoke break at the nipple and the angle the spoke enters the nipple is not nice, the nipple just doesn't want to sit at the same angle as the spoke.

Quote:

Originally Posted by mark03 (Post 16472502)
BTW you should add some hyphens in the subject, otherwise it may remain a small thread! :lol:

Good point, could easily be interpreted as "a small tread about wheel building". How do I change it?

BassNotBass 02-06-14 10:13 AM

Quote:

Originally Posted by mark03 (Post 16472502)
... BTW you should add some hyphens in the subject, otherwise it may remain a small thread! :lol:

"Let's eat grandma" "Let's eat, grandma"

mark03 02-06-14 10:27 AM

Quote:

Originally Posted by BassNotBass (Post 16472712)
"Let's eat grandma" "Let's eat, grandma"

Yes, this is the tagline to my favorite FB group, "Punctuation saves lives" :lol:

And apologies to the OP, I don't even know if you can change the subject; I was just making fun at your expense...!

mark03 02-06-14 10:33 AM

Quote:

Originally Posted by ThorUSA (Post 16472553)
Sapim Polyax nipple are somewaht conical shaped and they follow the spoke better than all others, why other peeps dont do that is a miracle to me.

Thor, I'm planning to use some Velocity deep rims (Aeroheat) which don't come with eyelets. Would you recommend adding some washer thingies? The Polyax looks good, but I wonder if they need a "bearing surface" more than garden-variety nipples.

Rob_E 02-06-14 12:20 PM

Quote:

Originally Posted by ThorUSA (Post 16472553)
only difference to large wheels
is the angle of the spoke coming out of the rim ....

Exactly. That's why Nuvinci recommends 1 X on small wheels: Large hub diameter + small rim diameter = wicked angles at rim if you put too many crosses in. I did the same thing when lacing a Nuvinci hub into a large rim. Their specs said I might be able to get away with a certain number of crosses, so I tried it. Broke spokes at the nipple until I relaced it with one fewer cross. Just what ThorUSA is describing.

I feel like some spoke calculators might supply the rim angle, so it might be useful to define what angles are too sharp.

For my part, with any wheel, I'm looking for the max number of spokes + the max number of crosses that can be done safely. My goal is the strongest possible wheel, and, while I'm not one for counting grams anyway, even if I were, the weight difference of a few spokes or shorter spokes seems so small that there's no point in even trying find a compromise between light and strong. I just go for strong. If want to lighten things up, I'll look at the hub, rim, rubber, or other bicycle components before I'll skimp on the spokes. It's probably overkill, but ask a lot of my wheels, and the weight cost is negligible to me.

Also, as I've found with my recent project to build a Nuvinci rim, the fewer the crosses, the shorter the spoke. The shorter the spoke, the fewer the sources for spokes. Although getting them custom cut remains an option.

ThorUSA 02-06-14 02:05 PM

Quote:

Originally Posted by mark03 (Post 16472776)
Thor, I'm planning to use some Velocity deep rims (Aeroheat) which don't come with eyelets. Would you recommend adding some washer thingies? The Polyax looks good, but I wonder if they need a "bearing surface" more than garden-variety nipples.

no need to do that ....
I use those on wood rims ( and carbon ) or very sloppy soft alloy tims .. :-) the areohead is a strong one and doesnt need them

fietsbob 02-06-14 05:10 PM

Brompton is 2 cross 12 ga thick spokes (the Rohloff is 1 cross in a 406 rim)

brass washers on the hook inside would deform more than the steel hub flange
so may dent the spoke less and fill some. the hooks got wider when most-all hubs became aluminum.

jur 02-06-14 09:48 PM

+1 on the spoke angle at the rim problem. I have broken a few spokes at the nipple end, just busy fixing SWMBO's Moulton due to that.
https://lh4.googleusercontent.com/-_...o/IMG_2665.JPG

I generally do 2x drive side, and straight at non-drive and front, the latter if the hub manufacturer approves of it.
https://lh4.googleusercontent.com/-w...-no/2012-01-17

seely 02-10-14 09:31 AM

Quote:

Originally Posted by ThorUSA (Post 16473432)
no need to do that ....
I use those on wood rims ( and carbon ) or very sloppy soft alloy tims .. :-) the areohead is a strong one and doesnt need them

^This. They are pretty much unnecessary on our "A" setction rims (A23, Dyad/Aeroheat, Aerohead, etc). The triangulated cross section allows for a thicker spoke bed, which really eliminates the need for washers.

cpg 02-10-14 11:53 AM

Quote:

Originally Posted by jur (Post 16474613)
I generally do 2x drive side, and straight at non-drive and front, the latter if the hub manufacturer approves of it.

That's an interesting idea Jur. Does it create any problems when truing the wheel?

jur 02-10-14 04:21 PM

Quote:

Originally Posted by cpg (Post 16483552)
That's an interesting idea Jur. Does it create any problems when truing the wheel?

None at all. Sheldon Brown suggested this idea of radial spoking on non-drive side, not sure exactly why any more, but it had to do with spoke tension and spoke breakages. Something about cassette hubs having asymmetrical spoking, resulting in quite low tension on the non-drive side. But I don't remember why radial was better.

cpg 02-10-14 04:32 PM

Thanks Jur, I will have a look at Sheldon's web site.

fietsbob 02-10-14 04:45 PM

Bike Friday did a Basket weave 1 cross on the Rohloff 32 hole .. 406 rim

When I asked , given the hub manufacturer was not recommending the woven cross ,
If they would stand behind their choice, and fix it if things like hubshell flanges going out happened,

they said they would, so I left it at that..


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