Cassette problems on a new Tacx Neo 2T trainer

I recently bought a new Tacx Neo 2T and I’ve set it up with my XC MTB for now. I bought a brand new SRAM NX 12s cassette because it’s an MTB cassette that was readily available and that’s fully compatible with the HG 11 body on the Neo.

I’m having 2 major problems with my setup though:

Videos and pics are here

  1. the cassette is VERY wobbly. It is fully tightened to the very best of my abilities. I’ve tried fitting an extra 1.85mm spacer (the current setup as shown in the videos) behind the cassette as recommended by SRAM for this specific combination of cassette and body. I’ve tried fitting 1, and then 2, of the spacers that come with the Neo assembly kit. I can’t fit anymore spacers over any of the combinations because then the stack becomes too long for the body and I’m no longer able to fit the smallest cog or the lockring. On one of the videos you can see that there is a lot of play between cogs - all the individual cogs have some level of play, but there’s even more of it between the 4th and 5th cogs (where the thick spacer is). On the other video you can see the wobbly effect that results while pedalling.

  2. the derailleur (a shimano XT) hits the trainer when on the lowest gear. There’s a troubleshooting section in the manual which addresses this exact issue, and as instructed, I’ve fit the 2 extra spacers behind the axle. Still the lowest gear completely rests against the trainer, and the second lowest is very, very close to it. Adjusting the limit screw will just make it impossible to jump to the largest cog, and (ignoring the wobble), it seems to otherwise sit just right for all the cogs - so it’s as if the entire assembly is sitting too much inwards.

Is there anyone who has tried fitting their MTB on a similar trainer, or perhaps even this specific cassette on this specific body? I’m terribly frustrated because I don’t know what I’m doing wrong and I’m not too mechanical savvy to start with, so I’m all out of ideas.

I hope someone can help me out! Thank you!

To anyone who might have similar problems in the future and stumble upon this post:

  1. The problem was that, in spite of what SRAM writes, and of what multiple posts throughout the internet say, you don’t actually need any spacers behind this cassette. Without the spacers, the lockring goes that much further in, and locks the cassette in place perfectly.
  2. The issue is simply an ever so slightly bent rear derailleur hanger that’s only barely noticeable while eyeballing. In hindsight, that also explains why shifting has been a bit wonky between the inner cogs while out on a ride.

I use that exact trainer, and have used it with two different SRAM MTB Cassettes. The difference though is I’m a SRAM drivetrain, using the Tacx XD / XDR body and first cassette (I think) was the XG-1275 GX Eagle. Second one is now XG-1275 T-Type.

So, it’s definitely possible with the XD / XDR Driver body and the right cassette. Can’t help you with the combo you’re trying though.

Regarding your first issue, I had that problem with my neo og last year. The problem was that the bearings in the free hub died. It seems like that shouldn’t be your problem if it’s new, but perhaps you can check that.