Hello, everyone,
Although I was concerned that the Zwift Hub and my road bike might be incompatible, I took the risk and ordered a Zwift Hub. Turns out: The Zwift Hub touches the carbon frame on one side.
As far as I know, that’s a problem and I shouldn’t ride it like that.
Does anyone have an idea for a workaround? I’ve thought about sanding down the piece on the Zwift Hub, but I imagine that’s not the best idea.
Add a spacer between the trainer and frame. More accurately: if you install a sleeve around the threaded section of the QR adaptor, it will reduce the depth it can screw into the trainer which results in the drop-out spacing being increased.
This is nearly par for the course with a lot of trainer and bike combos.
For reference, here’s a page on spacers for the Tacx NEO2T to facilitate disc brake clearance: Neo — Disc Brake Spacer – Tacx Faqx
EDIT - out of curiousity: which adaptor/spacer do you have installed? There’s one for 130mm dropouts, another for 135mm, if I recall correctly.
Many thanks for the quick response, this sounds like a great solution!
Quick follow-up question: Do you have any idea where to get such a spacer best? Hardware store or somewhere online?
Thanks in advance! 
Yeah, you’re on your own there.
My approach would be to measure the diameter of the threaded section of the adaptor so you know what the inner diameter of the sleeve should be.
I just measured the thru-axle adaptor from a Tacx NEO/Flux and come up with 16.76mm across the threaded section. If yours is the same (BIG if), you could source the Tacx sleeve, part T2844.15 and use that.
You might try an industrial hardware supplier or just cut an appropriate diameter section of metal pipe down. Bring the adaptor(s) with you and test fit.
Awesome advice, thank you very much! I am already on my way to the nearest hardware supplier. Very much looking forward to zwift soon!
Are you sure that you have used the right zwift hub adapter for your frame?
See you have managed your first couple of Zwift rides. Plenty more to look forward to. No looking backwards now !! 
I’m pretty sure yes! The Canyon Ultimate road bikes with rim brakes seem be known for problems like this.
You are using the smaller 130mm adapters and trying to widen it with shims.
Have you tried the 135mm adapters?
Yes, but it felt like it was “too wide” or at least wider than necessary. I think I’ll keep my current solution for a few rides and then examine the frame/dropout again more closely. At least for now this seems to work fine.
What was your solution in the end? I’m sure Zwift HQ would appreciate hearing as well so they could offer a sleeve for other users.
Hi @Dominik_Schaumburg welcome to Zwift forums.
Shuji from Zwift HQ here.
Officially, Canyon says that the rim brake Ultimate is not compatible with certain direct drive trainers where their frame will make contact.
Given the physical contact between your seatstay and the trainer - we would advise you stop use to prevent damage to your frame, and contact us for a return and refund.
How you sorted out this issue? I am on the same situation with an ultimate cf slx 2018 frame with rim brakes. Did you find the Tacx piece proposed here? T2844.15
If possible, please post some pictures
I ended up removing a few millimeters of the metal where it touches the frame with a grinder and fine sandpaper. This is hardly noticeable and seemed sensible to me. This way I don’t cause any damage to the frame and the damage to the roller trainer is so small that it doesn’t limit its functionality. All of this at my own risk, of course, I understand that both Canyon and Zwift have to be consistent in their communication in order not to be responsible for negative reports and consequences.
A single steel washer did the trick for me. The frame still drops down onto posts with no flex, still plenty of length to support, and no contact between chainstay and Hub.
any idea what size washer you used? have any pictures of the bike mounted? thanks. i have the same issue
