Tri-spokes etc

Sounds good! Are you going to make it ? :)

Are you going to make it ?

Ask again in 6 years :)

Are you going to make it ?

We're one step closer, I've done a quick and dirty sketch of a solution which leaves the hub threads intact so the wheel can be reverted to freehub configuration, and using a stock Shimano freehub body fixing bolt for attachment, so that part is £2.99 rather than a £50 custom job. You have to remove the NDS bearing to assemble it, so it's not a quick change, but that's a small price to pay.

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3 holes in the hub "shoulder" surface matched up to pins on your new extension?

Maths/engineering types feel free to correct this:

With 40Nm tightening torque on the M15×1 body fixing bolt, the force on the mating face is about 13kN. As two dry aluminium surfaces have a typical coefficient of friction of just over 1 and the mating face mean radius is about 16mm, that suggests the clutch effect will resist about 200Nm

For the commutenger case, a 100kg rider just standing on the end of a 177.5mm crank with a 66" gear generates about 140Nm at the hub

Conclusion: the safety margin is not sufficient to make the dowel pins a mere fail-safe, and to avoid fretting they will need to be a press fit in both parts

a stock Shimano freehub body fixing bolt for attachment

Looks good! Is there enough material in the fixing bolt shoulder to cut the dura-ace twinthread? or do you add material somehow.

and is it a classic fixing bolt or one of the new larger ones (which could fit a larger axle!) for newer dura-ace/xt/xtr hubs?

Conclusion: the safety margin is not sufficient to make the dowel pins a mere fail-safe, and to avoid fretting they will need to be a press fit in both parts

Idiot suggestion: What about 6 m5 bolts (it works for disc brake loads in a 44mm diameter pattern. (and drop the fixing bolt)

The fixing bolt (classic type) doesn't touch the original hub threads, it passes straight through from the NDS and threads into the adapter

Making room for a bigger axle would have been nice for weight-weenie purposes, but a 10mm steel axle is fine for solos with 120mm OLN (the bearings are quite close to the dropouts in this case), and not that heavy if a 138mm long hollow axle is used with M6 tapped ends for small fixing screws. For conventional fixing with a ~160mm axle and track nuts, weight-weenie concerns have obviously already been abandoned 🙂 A big axle only really makes sense with big bearings anyway, and you're pretty much stuck with 6001 on the NDS as the hub shell won't accommodate larger, and the DS might as well match even though there is a way of getting a big bearing to play nicely with a 6-bolt sprocket if the drop the bore register.

6-off M5 bolts would certainly take the load, but they would have to pass through the DS bearing housing so that would be weakened by having counterbores for the bolt heads intersecting the outer race fitting bore. The problem is that we're starting with the fait accompli of the Hed hub, which has very little spare metal. If we had freedom of action, we'd just make the hub shell big enough to take the sprocket fixing bolts directly, and the adapter wouldn't be much more than a spacer.

Simplified where it needed simplification, #tartmode where people can see it

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Since it is an aero wheel wouldnt it be better to have a solid block with the disc bolt pattern (maybe with a rounded edge toward the wheel)
ala:

and holes between the disc holes for weight savings..

for the aeros... less disturbance of the air

What diameter are the pins (and the holes for the pins)?

wouldnt it be better to have a solid block with the disc bolt pattern

It's too far from the main wheel body to blend, and the air is already fucked by the chain where the sprocket mounts. A plain disc would be simpler to machine, but I like pretty things 🙂 On a CNC it's not much effort to do the shaping, obviously if you were doing it on manual machines you wouldn't bother.

What diameter are the pins (and the holes for the pins)?

5.00mm pins, 4.99mm holes 🙂

Ok great! What is the price? :)

for the aeros

For the aeros, use a disc wheel. I don't think anybody thinks a H3 is better in the rear than a disc. 2-Spoke think their wheel is, but it has 30 years of development on the H3

What is the price?

More than a Chinese track disc off of Aliex 🙂

I don't think anybody thinks a H3 is better ... than a disc.

Specialized 1990 did: :)

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Added bearings. I already have spare 6001 SKF in the part bin, so there's some money this project won't need to complete 🙂

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NDS "cone" flipped to keep the axle threads as far from the high bending stress as possible, dropout bearing faces increased for similar reasons
https://autode.sk/2ZiS9BH

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