Stumbled upon this yesterday from KMC. Appears they are releasing a new version of the X12 chain to be compatible with SRAM AXS as a replacement for the flattop. Curious how they are saying its compatible with multiple manufacturers as SRAM Flattop has smaller rollers. Sent KMC an email on availability and they said Q4 of 2022. Page from their site does show AXS system running it(not that that necessarily means it works WELL). https://www.kmcchain.com/en/series/x
I have used gen 1 12 spd chain on AXS works fine on the rear and I have Rotor AXS chain rings shifts fine up front.
I did try a sram flat chain on the rotor AXS chain rings , did not work.
The real test is will it work with the sram chain rings.
Many chains WILL shift. But with roller sizes being different(flattop has bigger rollers) the contact size on the cassette/chain rings will be different and you’ll be creating premature wear.
I hope we see these state side soon. I have 2 bikes with Rotor rings and I notice sometimes the chain “sticks” a bit on the rotor chainring. Maybe these will be just a touch smaller and not stick?
Unfortunately tied to Rotor rings because of a power meters and BCD fitment.
I use Rotor AXS rings (SRM Origin cranks) with SRAM flat top chain… seems to be fine so far.
Sounds like marketing at it’s best. Use our chain or you will die.