12 speed etap front derailleur on 11 speed drivetrain?

[tripmaster]

Can I use the AXS Force etap front derailleur on 11 speed drive train? Feels like there shouldnt be a problem, but the 12 speed chain is slightly narrower than the 11.

I wanted to run 11 speed sram red rear, and force etap shifters+force front derailleur.

[kppolich]

https://cyclingtips.com/2021/11/sram...ed-etap-users/
Top comment: Pair the shifters and FD like you normally would, as long as the shifters are 12sp AXS too.
Battle will be if you are using 11sp shifters as they can't be paired to 12sp stuff, only 12sp is backwards compatible.

Here's a useful doc capturing compatibility strictly for AXS:
https://www.sram.com/globalassets/do...bility-map.pdf

[thegunner]

Originally Posted by tripmaster

Can I use the AXS Force etap front derailleur on 11 speed drive train? Feels like there shouldnt be a problem, but the 12 speed chain is slightly narrower than the 11.

I wanted to run 11 speed sram red rear, and force etap shifters+force front derailleur.

I'm pretty sure the derailleurs have to match and the shifters don't matter. it's why the 11s FD commands such a high price right now.

[kppolich]

Originally Posted by thegunner

I'm pretty sure the derailleurs have to match and the shifters don't matter. it's why the 11s FD commands such a high price right now.

Yep, a few hard no's here:
https://weightweenies.starbike.com/f...5367&start=180

[tripmaster]

Originally Posted by kppolich

https://cyclingtips.com/2021/11/sram...ed-etap-users/
Top comment: Pair the shifters and FD like you normally would, as long as the shifters are 12sp AXS too.
Battle will be if you are using 11sp shifters as they can't be paired to 12sp stuff, only 12sp is backwards compatible.

Here's a useful doc capturing compatibility strictly for AXS:
https://www.sram.com/globalassets/do...bility-map.pdf

Right - I know Force eTap can pair with 11speed rear (I have one); if I can use a 12 speed Force front, that's the tricky part.

[tripmaster]

Originally Posted by kppolich

Yep, a few hard no's here:
https://weightweenies.starbike.com/f...5367&start=180

Well...Fuuuuu
:-(

[kppolich]

To me, it makes sense that 12sp Force AXS shifters can pair with the 12sp AXS Front Der no problem Hold the pairing buttons and go.

The battle will be if you can have a 12sp FD and 11sp RD. Couldn't hurt to try and report back.

Honestly, I'd like to see a nicer compatibility chart for 11sp/12sp AXS stuff.

[thegunner]

Originally Posted by kppolich

To me, it makes sense that 12sp Force AXS shifters can pair with the 12sp AXS Front Der no problem Hold the pairing buttons and go.

The battle will be if you can have a 12sp FD and 11sp RD. Couldn't hurt to try and report back.

Honestly, I'd like to see a nicer compatibility chart for 11sp/12sp AXS stuff.

or let me run 12s FD/RD with old etap shifters. I have a spare RD, but I don't have a spare FD sigh.

[whatshubdoc]

Originally Posted by kppolich

To me, it makes sense that 12sp Force AXS shifters can pair with the 12sp AXS Front Der no problem Hold the pairing buttons and go.

The battle will be if you can have a 12sp FD and 11sp RD. Couldn't hurt to try and report back.

Honestly, I'd like to see a nicer compatibility chart for 11sp/12sp AXS stuff.

It sounds like this is possible. I don’t think one derailleur is the “master” over another is it? If so, then yea it might pose an issue.

[rice rocket]

RD is always the master.

[yinzerniner]

Originally Posted by whatshubdoc

It sounds like this is possible. I don’t think one derailleur is the “master” over another is it? If so, then yea it might pose an issue.

See doc below, seems to imply that since the RD is the “master” it only has compatibility with red/force axs shifters and NOT the axs FD.

https://www.sram.com/globalassets/do...bility-map.pdf

[tripmaster]

Interestingly SRAM sent this back to me:

"I apologize, but this is not possible. The AXS front derailleurs are designed to work with the AXS chainring spacing and 13 tooth difference between the inner and outer chainrings, so they have differences in geometry that would not allow them to shift 11-speed systems smoothly, even if there was a firmware update to allow them to communicate with each other."

Doesnt talk about the actual shifting control, but I think I get the message.

:-(

[ikecycke]

If you do get the derailleurs to work together, the front AXS derailleur will shift with standard chainrings just fine, regardless of what Sram says. I was running Force AXS shifters and derailleurs with non-Sram 12-speed cassette, KMC chain, and 53/39 Praxis chainrings.

The problem you could run into there is getting the front derailleur high enough if the frame uses a braze-on, since the mounting bolt on the derailleur is positioned quite high. The first frame I did this on used a clamp on front, so it wasn't an issue there, but I recently tried on a different frame and couldn't even clear a 52 large ring. One of the newer 2-hole mount Red AXS derailleurs would fix that, but they're pretty tough to come by.

[hmsolomon]

Originally Posted by tripmaster

Interestingly SRAM sent this back to me:

"I apologize, but this is not possible. The AXS front derailleurs are designed to work with the AXS chainring spacing and 13 tooth difference between the inner and outer chainrings, so they have differences in geometry that would not allow them to shift 11-speed systems smoothly, even if there was a firmware update to allow them to communicate with each other."

Doesnt talk about the actual shifting control, but I think I get the message.

:-(

Thanks, I almost went for an AXS to replace the FD for eTap 11 speed. FWIW - I'm about to buy my 3rd SRAM Red eTap FD. #1 and #2 both developed seized upper limit screws. Blue Loctite did not solve it on #2. I'll try brass or titanium limit screws for #3.