SRAM AXS cassette/derailleur compatibility SETUP

Hello community
I Need your help to setup my SRAM components.
Recently I bought a new bike with SRAM AXS.
This bike have a Sram Eagle Cassette XG 1299 10-52t.
My Smart Trainer I have installed a SRAM Eagle NX 11-50 if i´m not wrong.
But when I put my bike in my trainer and I start pedaling all the changes make noises or jump unless y put the chain in the smaller COG 11.

My question is
How can I configure/setup my AXS rear derailleur to use the NX Cassette when I use my trainer and when I use my bike out side.
I search into the app but i can´t find any option.


You likely have to micro-adjust the derailleur and it’s super easy in the app.,shifting%20to%20an%20inboard%20cog.

1 Like

It could be the micro-adjustment noted above.

What chain is the bike using? Is it the Eagle chain, or the road AXS chain (flat top on the links)? The two systems are incompatible (according to SRAM). In reality, some people have mixed with passable results (noisy and clunky, but works well enough for a trainer).

Could also just be that it’s a new cassette. Sometimes if I’ve added a new cassette, with a used chain, the combo is noisy for a few rides. I wouldn’t do this normally, but something I’ve added a wheel set to my rotation or similar.

Have you installed a spacer behind the NX on the trainer?


No, I do not installed any spacer
I just bought the NX Cassette and install it.
Do you think maybe that is the problem?
I not tried yet the link above

Likely your problem. The PG-1230 installed on a HG splined 11spd hub needs a 1.85mm spacer.


Thanks for the clarification.
I’ll tell you, when I bought the trainer, I also bought the SRAM XD-R Body.
Do you think that if I install that body and install the cassette, is it still necessary to add the spacer?
I don’t remember if that spacer comes in the box or if I have to buy it.

Yes, if using an xdr hub, you need the spacer. If using xd (typically Mtb), no spacer needed.

I am a little confused.
And to clarify the configuration a bit.
I use the Trainer with my MTB, so the cassette I am currently installing is a SRAM Eagle NX 11-50 12v.

Option No.1
If I install the SRAM XD-R Body I need the spacer. it’s right?

Option No.2
Currently the cassette installed is a 12v Eagle NX (MTB) on a SHIMANO/SRAM 9-11 cassette body so I understand I don’t need the spacer.

So for option 2 there should be no problems, but that’s where my confusion lies, because the chain jumps a lot and comes out or doesn’t mesh well and I basically have to use COG11

SRAM Eagle NX 11-50 is Shimano Hyperglide compatible. It’ll need a 1.85mm spacer when installed on a 11spd Shimano Hyperglide freehub. It’s not compatible with a SRAM XD/XDR freehub body.

It’s in the SRAM tech doco but they never use the term ‘Shimano’ or ‘Hyperglide’. iirc they use ‘splined’ as the term.

In short - Option 2 - Needs a spacer installed.



HG-11 freehub and 11s HG mountain (or wide road) cassette = Spacer
HG-11 freehub and 11s HG road cassette = No Spacer

HG-11 freehub and 12s HG mountain cassette = Spacer
HG-11 freehub and 12s Microspline cassette = does NOT fit
HG-11 freehub and 12s road cassette = ??? (not sure, probably not)

XD freehub and 12s XD mountain cassette = No Spacer
XD freehub and 12s XDR road cassette = does NOT fit

XDR freehub and 12s XD mountain cassette = Spacer
XDR freehub and 12s XDR road cassette = No Spacer

It sounds like you have an HG-11 freehub and a Sram HG-compatible 12s cassette, so you need the spacer. Without it, the cassette can move laterally ~1mm. If you push it left/right, you should be able to feel a slight wobble without the spacer. It will work, but that slight wobble will make it shift poorly and make noise.

1 Like

This spacer that you mentioned is the same it comes with the XDR body?
If thats correcto I suppose I just need to put into the body and reinstall the cassette right?

Looks like the Shimano 11spd/10spd spacer is the same as the SRAM XDR/XD spacer, 1.85mm.

1 Like

First of all sorry for the delay.
Today I had the opportunity to get the tools to be able to install the spacer.
Indeed, the spacer that comes in the SRAM XD-R Body kit (which I bought at the time) has worked wonderfully.
Thank you all for your help in solving the problem.
To clarify how the setup was
here I comment.

Tacx neo 2t
OEM Shimano/SRAM 9-11 cassette body
Spacer 1.85
SRAM Eagle NX 11-50 Cassette
Upper Shifting and Down Shifting running smoothly