Wheelbuilding / Wheel Building / Wheel build help

This is exactly the feedback I need, real world scenario's! thx!

Radial front, low flange hub, 20 spokes. Heads in or out?

Heads in or out?

Depends

Heads in: better bracing angle, marginally stiffer.

Heads out: marginally more aerodynamic, looks better.

LB rims arrived today. The stated ERD is 'not including nipple head dimension', so when I measure ERD it comes out higher - which figure should I be using? If I only include the nipple up to the shoulder/bottom of the head, ERD is pretty much the same as what LB say, just 1mm higher.

Obviously, the difference between the two ERD figures makes quite a difference in spoke length.

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Use the figure as measured, then round down on the spoke lengths. LB seem to measure just to the inside of the rim, without allowing for the part of the spoke which should be inside the head of the nipple, so assuming you want the spoke to be roughly flush with the top of the nipple you would expect to add a few mm's to their measurement to get the true ERD.

I've ordered everything for a DIY truing and came to a grand total of €70. Bit more than I was planning to spend but should be heaps better than what I could buy for that money (measuring clock, compatibility with QR, 12mm TA, 15mm TA, enough clearance to not have to remove 29x3" tyres).

Cool, thank you. That's what I was thinking was probably correct, but wanted to check before I speak to my spoke guy! He can do odd numbered cx ray, but I expect it'll cost more as he has to cut them - will evens be ok? i.e. 256, 252, 266 and 266? And finally - brass nipples over alu, and 12mm?

LB seem to measure just to the inside of the rim, without allowing for the part of the spoke which should be inside the head of the nipple

To be fair, they do state that that's the measurement they're giving you.

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They do, although the 'not including nipple head dimension' could be a bit clearer as to what they're talking about. Once you know it makes sense, but it's not exactly obvious to the uninitiated.

I've only ever used evens lengths. 1mm really isn't going to make any difference - as long as the spoke isn't 1mm too long.

I'll probably get cast out as a heretic for saying this, but I much prefer good ali nipples to brass ones. I've never had any problems with Sapim Polyax alloy nipples (apart from one which broke after having been marinaded in latex/ammonia sealant for several years), and I've had quite a few problems with brass nipples binding, breaking and releasing suddenly for no reason. My default choice is 14mm Polyax alloy nipples.

That's what got me. When I actually measured it it became clear what it was, but I hadn't clocked it when I ordered the rims. Luckily I waited for them to arrive before ordering spokes!

That's great, thanks.

I much prefer good ali nipples to brass ones. I've never had any problems with Sapim Polyax alloy nipples

To be fair, they do state that that's the benefit they're giving you 🙂

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To be fair, they do state that that's the benefit they're giving you

And for once, it's true.

Any cunning ideas on how to measure the ERD of rims that don't have holes in the rim bed for accessing the nipple heads?

My current plan is to measure the ID of the rims, measure the thickness of the rim wall around the valve hole, and then add a few mills for the spoke heads, but better suggestions welcome.

I started a wheel-building project a few years ago but it went tits up and has been sitting gathering dust for ages and lockdown seems a sensible time to start... I have a hub (Sturmey Archer S2C kick shift 36 spoke) and a range of different spoke lengths (have about 40 spokes in either 292mm and 296mm), and want to find a rim to marry the two together.

I've spent the past few hours on wheel building calculators, my brain is fried and I'm no closer to figuring it out... I have hub measurements (and spoke sizes), but when I try to calculate this with the type of rim I might want (something like Mavic Open Sport), the spoke required are too long with 4X or too short with 3X. Any suggestions? Any help greatly appreciated!

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You could go for the build that leaves you with too long spokes (how much too long btw?) and just get them shortened by your lbs if they have time and are open :)

might aswell go for the fancy CSS stuff

Harder to find now these days!

Homemade design?

I'm trying to replicate this.

You’re finding this hard because spoke length calcs calculate spoke length based on hub & rim dimensions, you want a rim erd calculator that gives erd according to your hub and spoke dimensions. Which doesn’t exist.

Try entering various erd measurements til you get one that shows @3x ~290mm or @4x ~294mm. Then find a rim that is that erd or near, a bit over that would be fine as you’ve already aimed at a -2mm rounded-down spoke length.

Are those^ your actual hub measurements? (though we can’t fully see the number in left flange>centre box) someone very bored, maybe me at about 3pm this afternoon say, might try to help you find your rim.

If those are your numbers^^ (I’m approximating a L f>c @29.5) your longer spokes, @ 4x, want an erd around 596 - 598

Velocity Dyad 596
Rigida Andra 30 598

What is the go-to 26" disc brake rim for touring bikes available in 32H? tubeless would be a plus.

aka what is the Kinlin XR31 of the 26" wheel world?

I was a fan of the halo freedom disc on my polo bike, they're not tubeless but they were made by kinlin.