Wheelbuilding / Wheel Building / Wheel build help

I’m struggling to find a consensus / up to date info on line. How many spokes should a road disc wheelset have? Most places seem to agree 24/24 and not radial to deal with braking forces. If I’m using 30mm ish alloy rims and weigh ~75kg, could I go down to 24/20? Also realise I’m probably overthinking it but like to increase my understanding of it all :)

if you are after silver, I've got some Ukai rims for sale here

I wouldn’t go less than 24 personally, and even that seems low. I think with 20 I’d start worrying about load limits, rotor sizes, braking hard etc. 😅. But maybe I’m over cautious…

I’ve seen Vision do a 35mm rim with 21 up front, does the additional rim depth help? Or is it still better to go for a higher number

Vision do a 35mm rim with 21 up front

21 spokes suggests 14 on the disc side and 7 on the other side, which is nearly as good as having 28 spokes.

You can make 20 spoke disc brake wheels, but it's not really worth the effort. If you're not racing, you might as well use 32 spokes, because the performance gain from using 24 is tiny but the durability gain from using 32 is huge.

the performance gain from using 24 is tiny but the durability gain from using 32 is huge

But the vast majority of broken spokes I've come across have fatigued from low tension. If the rim is strong enough in the nipple bed for low spoke counts, IMO&E you get a more durable wheel with fewer spokes, for the same counterintuitive reason that skinnier spokes build more durable wheels: it prevents spokes going slack.

That reasoning also says that triplet lacing is probably better on a dished wheel. And when considering front braking load, which will certainly exceed driving load on the rear, triplet lacing makes a lot better use of the spokes compared to standard semi-radial.

I reckon 21h is a pretty good number for front and rear, for medium strength rims (carbon, or at least a pound of ally), under a medium weight rider, on an unloaded bike.

You can make 20 spoke disc brake wheels

I was wondering where you'd find the hubs.

wondering where you'd find the hubs

They exist, I have one. I think the shop probably special ordered a batch from a Taiwanese OEM.

Can you easily replace a 7 speed freehub with an 8 speed or more freehub?
Like in this video.

https://youtu.be/V8Xnc6KrEqk?si=CouHMKraNfKqlBmI

I've seen a lot of conflicting write ups

Sure. Although the mating splines on some of the later cassette bodies are different, watch out for that. And that 10mm allen sleeve holding it on can be pretty damn tight... I have a WH-9000 which I tried to crack apart, to no avail, and that's with the allen key in a vise and me hauling on the wheel for all I'm worth. But I've undone probably half a dozen others, so it should be doable.

You'll need to sort out the OLD and dish, of course.

easily

As kimmo implies, "easily" is probably not the word. I'd say in most cases it's better to start afresh with a whole new hub.

Yeh, I think I'll try and source a late 90s early 00s rear mtb wheel instead. I think that's when the upgrade to 8+ speed took off.

Hm, I reckon rebuilding the wheel would only be easier if you can't crack that sleeve. If you have the right spacer and a cone wrench, re-dishing the wheel is pretty easy as long as the rim is straight.

Much easier to just get another wheel, of course...

Finally ordering a spoke key or three. So are the brands all the same and are the pro ones longer lasting.

are the brands all the same and are the pro ones longer lasting

🤷
They're cheap to replace if you ever wear one out

True as I lost more of the spokey ones that I have worn out.

Ended up buying the rexen and kaul 3.25, 3.40 and the ice tools 3.45 spoke wrench.

https://www.youtube.com/watch?v=7m-vnhh7PbM

Wheelbuilding with Berd spaghetti spokes

Ignoring the biz case and cost..

Have a Hope Five20 straight pull 24/24 wheelset with RS4 Hubs.
Rims are 19mm ID.

Would moving the hubs onto carbon 38mm deep, 25mm ID be OK with a 24/24 setup?
I presume they'd be stronger?

Might get used for the odd bikepack/tour, total system weight < 100kg.

Would moving the hubs onto carbon 38mm deep, 25mm ID be OK with a 24/24 setup?

Yes

Perfect

Would moving the hubs onto carbon 38mm deep, 25mm ID be OK with a 24/24 setup?

I presume they'd be stronger?

Struggling to imagine a reason that wouldn't be okay. If a disc wheelset, nice carbon rims are superior in every way, except perhaps the way they respond to being destroyed in a crash, which might cause a bit of a hazard with the splinters.

Out of interest what’s bad about the business case/ cost? Aside from the extra cost of bladed spokes due to straight pull hubs? I’m looking at similar

Out of interest what’s bad about the business case/ cost? Aside from the extra cost of bladed spokes due to straight pull hubs? I’m looking at similar

Nothing but in reality, I can get away with what is there and keep riding them. However, the front rim is dinged, they don't setup tubeless nicely and are narrow. I'll drop you a PM, have a rather good discount code for LB (if it works).

Ever since Shimano started busting out all those 16/20 bladed straight pull wheelsets, I've thought that should be the new default for a nice wheelset... Imagine Shimano, instead of coming out with 37 slightly different varieties of them, had only changed them enough to refine the details, and actually made spares available including rims...

It might have established a new standard like ye olde 32/32, and custom-built wheelsets made with new parts could have continued to be a thing beyond the tiny number of 20th century style builds which persisted.

TBF they did make spare rims / spokes, it's just that they were so expensive it was almost cheaper to buy a new set of wheels than replace the rims / spokes / freehub