Not sure that is true. I was under the impression that the dropout spacing for disc brake wheels is wider.

I'm curious...

XDR is just a SRAM's name for one of their lines of road hubs isn't it? I don't think that just because other brands don't use that term that their hubs won't fit in your bike.

Or does XDR fit in a narrower dropout spacing than other typical road hubs with disc brakes?

Though maybe a moot point since you've got a hub ordered.

XDR is SRAM 12-speed Road with a XDR freehub. XD is Mountain. Shimano 12-speed is Microspline, I believe. I don't think Shimano really sells aftermarket high-end hubs maybe outside of Shimano setups for Shimano group sets. I wanted totally silent so went with Onyx.

So the hub has to be correct for your dropouts, but that does not mean you can’t use a hub that works with a disc, and still put rims on it with brake tracks for rim brakes.

in our example, our tandem has 135mm spacing, and has both mounts for rim and disc brakes. We have wheels built with 240 DT hubs, that can accommodate a disc, but are laced to rims with brake tracks for rim brakes.

So if you want to build a wheel for rim brakes, the issue for the hub is not whether it’s rim or disc; it’s whether it fits your dropouts.

And for many hubs today, including DT 240’s, they can fit different dropout spacing depending on what end caps you use.

So again, the issue is dropout spacing, not whether it’s rim or disc.

^^ and if your bike has wide dropout spacing, there is no reason, you can’t buy a hub with disc brake capability that fits your dropouts and lace a rim to it with a brake track.

Sure, I think you can put rim brakes on a bike configured for disc brakes. Just mount the calipers, I guess. Assuming there is a mounting hole. But the other way won't work. My frame is setup for rim brakes, thus the narrower spacing between the dropouts. I can't just take off the disc and put the wheel in; won't fit. Too wide.

Not talking about the actual rim, it's the hub that is the problem.

Somewhere here on BF I started a thread asking that question and I got many helpful answers.

Hah. Was going to point out you can easily lace a 24h rim to a 32h hub if it's not straight pull.

hahaha that would drive me insane, especially on my Moots.

I believe the definite answer is to be found here:
Rule 23- // Tuck only after reaching Escape Velocity.

re-greased my rear hub again today, made a comparison video to see how much louder/quieter really is. same speed, same phone, from the same distance plus or minus an inch.

https://vimeo.com/858476818/2eb535c703?share=copy

Definitely quieter. I'll do this for my DT240EXP and same after I get the Onyx build done.

I used Shimano Ultegra "Tri-color" hubs on all the wheels I have built for my own use over the past few years. They look nice, they hold up really well, the seals are great, and they are very quiet. You can still find good deals on lightly used or NOS on eBay.

I grease the teeth and pawls on Phil Wood hubs with Phil Wood grease and it remains dead silent for two or three years. I've heard speculation that the pawls stick in the unengaged position from cold temps but I haven't experienced that at 12 F (-11 C). Maybe it happens at colder temperatures.

So the hub swap is done. The wheel went from a high-pitched chainsaw sound to..well, complete silence. I mean there is zero sound and it is an incredible experience. This is my thing going forward...gravel, MTB, road, and fat. The Onyx drag is super low since there are no teeth or ratchets clicking each other but the silence is just beautiful.

Now in the paceline, the lead won't hear you about to crash into their rear wheel when they slow up too fast. <grin>

I'll put some curb feeler type of things off the front of the handlebar. That should help.