Loud grinding on Zwift Hub with SRAM Rival Etap AXS with 12-speed

Hi together

I have a SRAM 12-speed etap AXS shifting unit. I tried to install it on a Zwift Hub and use the XDR adapter and a new cassette (the same I use on the bike SRAM XG1250 10-30). However, the “grinding” noise is really loud and does not sound “healthy” and seems to come from the chain (also I had the bottom bracket under suspicion). The bike is “quite” new and all parts have been used 800km. Guess, thus it should not be the chain. Unfortunately I cannot add a video/link to this post…

I already tried several steps:

  • installing bike several times
  • re-install new cassette on Zwift Hub
  • micro-adjustment of sram etap
  • tested installing Cassette with spacers (which shouldn’t be required as it is a 12-speed)

Nothing has so far been led to less noise… Hopefully someone has a solution. The last idea I have in mind is to install the cassette of my bike on the hub to see if that works.

It seems that the Zwift hub is not spinning the cassette smoothly but seems to have some “bumps”. In addition, I also installed the cassette of my bike. Whereas the sound was not as loud as the new one, the grinding is still present.

In addition I contacted the support team:

  • I wrote a mail (including video) to the support team and got a first response within 1-2h telling me that it looks/sounds like an issue of the unit and that me request is forwarded to the main support team. That really sounded promosing
  • main support team sent me a mail that the were not able to open the video link (which still works) so I recorded a new short precise video and sent it as an attachment 3 hours later
  • since then (3 days ago) no answer and no reaction from the main support team…

I am really disappointed as I want to start my indoor-training (weather-wise I do not want to bike outside) and seem to be blocked by a hardware issue…

Unfortunately it also seems to be hard to find another way to contact Zwift except via mail (support@zwift.com)

Also installed the cassette of my bike, whereas the sound in general was not as loud as with the new cassette it still was present.

Based on a new video I took it also seems that the Zwift hub is not spinning smooth and seems to slightly “wobble”

I also contacted the support team via mail:

  • first reaction from support team after 1 hour telling me that based on the video it seems to be an issue of the unit and request is forwarded to Zwift main support team
  • response from main support team 4h later: sorry we cannot open the video please send again
  • I sent a response including the video as attachment 4 hours later. Since then (3 days ago) I did not receive any message anymore.

Is there any contact possibility (phone/chat/etc) to speed-up the process?
I really would like to start my indoor training as whether-wise cycling outside is not an option.

Hi Martin,

I have the same issue.
How did you solve the problem?

Hi Lina

After “endless” communication with the support a new xram xd/xdr freehub body was sent. This reduced the noise dramatically. I would not have thought that this small part has such influence :sweat_smile:

Also using the Zwift Cog is working with SRAM nicely and is currently the setup I am using.

If you habe other questions just write.

Cheers
Martin