AXS Force Cassette and Standard 12 speed Chain Compatibility?

I'm new here so let me first say "Hi!"

I am working on a new gravel build and was going to make it a 1X mullet but I am really not a 1X fan for gravel - I know this is a sensitive subject but I am definitely building this bike 2X. I ride a lot of road to get to my gravel and this build is being designed for both.

What I'm hoping for with this build:

• Easton 36/40 Chainrings
• AXS Force 10-36 Cassette
• KMC X12 Chain
• SRAM 10 Speed Rear Derailleur
• SRAM Force 11 Speed Hydro Shifters with Ratio 12 Speed Upgrade Kit

I would like a 36 tooth cog in the rear for the tough days. I am not a big fan of the 11-36 spacing for my road rides but do like the 10-36 AXS. I have not purchased wheels yet so the driver is of no concern at this point.

I called Easton and their 2X chainrings are not flattop compatible so my first concern is running a standard 12 speed chain - like the KMC X12 - on the AXS cassette. I have heard there has been some success with this but hoping for additional feedback - anyone have any success or failure with this?

If the chain is indeed compatible I am thinking of installing the Ratio 12 speed upgrade kit and using a long cage 10 speed SRAM XO rear derailleur (with exact actuation) that I currently have. Ratio kit is here if anyone is interested. Black Water Cyclist on YouTube has had come success with this but that just one source, albeit a pretty good one...

Any feedback on what I have planned would be much appreciated.

Lee

Given the intercompatibility of Force AXS and Eagle RD/cassettes I would have assumed you could swap one for the other. However, found this thread where someone is suggesting that the spacing is not the same. https://www.mtbr.com/threads/close-range-12sp-cassette.1102871/post-14084347

So ... I guess I don't have anything of value to add, except to say that I'm running the Ratio conversion in a 1x setup (with GX Eagle RD) and enjoying if a lot.

bearlyfinish wrote:

... Expect 10-50% of typical lifespan.

Well that’s disappointing information...

I didn't read the original close enough to realize you were also hoping to use a 10sp RD. I know that for SRAM road 10 and 11sp RD are interchangeable, but is that also true for MTB 12sp (which is what the Ratio conversion will be doing)? I imagine you did research that, but I wasn't aware those were the same.

Too bad about the reports of degraded cassette life. Especially with those fairly pricey cassettes.

Yes pushstart the 10 speed MTB and road rear derailleurs use Exact Actuation. When SRAM went to 11 speed, and now 12, the MTB shifting changed to X Actuation. Ratio does make an 11 to 12 speed pull ratio adapter that attaches to the RD but it only works with sram 1X derailleurs - and I want 2X.

Embargo is finally lifted. Why not look at Rival AXS for 2x 12 speed?

dangle: I was wondering when SRAM would finally release Rival AXS and it is certainly on my radar but I have all the components, except for the cassette and chain, for the bike I'm working on, so to spend ~$1,500 now is just not in the cards. It may make for a nice upgrade though.

On another note I heard that some gravel riders are having issues with mud and their flattop chain. I guess the narrow spacing doesn't shed the mud so well.

I suppose it would add up a little bit for the full 2x build. The 1x 'mullet' build with a gx axs rear derailleur and whatever chainring you want to use on any crank sure looks tempting. 

Totally agree. I'm not keen to replace my 2  Quarq cranksets to support the latest proprietary chainrings. And if I can avoid the flattop chain, I will. But love the idea of a Rival AXS + GX AXS mullet.   I wish SRAM made a 10-42 or similar 12sp.  I've read conflicting reports of using Shimano cassettes, though my bigger problem is that none of my hubs support microspline. I imagine that is coming soon for Hope (or maybe here already when I go check again) but less likely to happen for my SRAM 900 hubs