All direct-drive smart trainers on the market today ship with a Shimano HG (hyperglide)-compatible freehub, because this meets the needs of many cyclists, especially roadies.
But what if you have a mountain or gravel bike using one of the increasingly popular 1x 12-speed SRAM Eagle groupsets? In that case, you have two options:
- The more complex and expensive option: purchase an XD/XDR freehub body from your trainer manufacturer (here’s one for Wahoo KICKR, and here’s one for Tacx NEO), and install it. Then purchase and install a 12-speed cassette to mount on that new freehub body.
- The simpler option: purchase and install a lower-spec cassette like the SRAM NX Eagle PG-1230 which can mount on your existing HG-compatible freehub. This lower-spec cassette is heavier than the high-end counterpart, but that doesn’t matter indoors. (It’s also worth noting that the smallest cog on the PG-12320 is 11 tooth instead of the 10-tooth of the higher-end cassettes, which may affect your ability to push hard in sprints or on descents in Zwift.)
Shane Miller, our favorite Zwifting Aussie, talks us through it:
Questions or Comments?
Are you running a 12-speed setup on your direct-drive trainer? How did you do it? Share below!
The problem with using a MTB on Zwift is the chainring size. You will spin out if you are not in ERG mode.
Truth! I wish Zwift would add a “base resistance” setting to people could bump up the resistance and not spin out on MTB setups.
Disappointing after they made such a fuss putting a MTB on display for their steering release a couple of years ago. MTB’s and CX bikes are basically u unusable on Zwift for everting but a workout.
Thank you for the information…any update if there is a Shimano splined compatible rear cassette with 12 speed to use on my SRAM etap drive train on my gravel bike?
There is another part needed to make the Zwift Hub work for Eagles (and I’ve read other DD trainers as well). It’s the SHIMANO 11-Speed 1.85mm Low Spacer (FW8991)
https://www.amazon.com/gp/aw/d/B00BO4X1SE?psc=1&ref=ppx_pop_mob_b_asin_title
using the PG 1230 alone has poor shifting results. You can see in SRAM’s literature it is needed. See page 7 here: FYI the Zwift Hub is an 11 speed splined body and the spacer is called for. https://www.sram.com/globalassets/document-hierarchy/user-manuals/sram-road/drivetrain/user-manual-cassettes-and-chains.pdf
I have a eagle AXS and it shifts perfectly with Eric’s hack above, AND the spacer. Good luck
Can I use this cassette (SRAM NX Eagle) with my Sram AXS?
Hey Eric,
I’ve just bought a Wahoo Kickr V1 to help my son with post op recovery.
I have a Scott Spark MB with SRAM MX 12 rear cassette. I need to get a compatible cassette for the Shimano hub on the wahoo.
Am I reading this post as my fix? And the PG-1230 is the part I need to put my Scott on the Wahoo? Do I need the spacer mentioned below?