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dbnm
09-16-2020, 05:26 PM
This came up here before so I just wanted to post a little additional info.

The regular Force AXS rear derailleur will work with the wide (10-36) cassette.

See here
https://blog.3t.bike/2020/05/14290/sram-force-axs-wide-gearing-hacks-gravel-bike-tech/

I think I am going to try this out.

R3awak3n
09-16-2020, 05:57 PM
someone here said he bought the wide and normal and said they are the exactly the same but one has a longer B screw so he just bought a longer b screw and said it worked perfectly. Don't remember user name but I bet he will chime in

Dave
09-16-2020, 06:24 PM
The wide RD does not have a longer cage, so it does not have any more wrap capacity, but the main pivot mount is longer. To get all cogs to shift properly, the B screw must be adjusted for minimal clearance with the upper jockey pulley, when shifted to the little ring and 36T sprocket. If you don't, the 10-11-12 sprockets may not shift properly. I made a longer B screw from an M4 x 25mm button head screw, with the head ground down to a smaller diameter, but later found that the original screw was just barely long enough for my bike.

dbnm
09-16-2020, 06:50 PM
Any chance you can post some photos?

Dave
09-16-2020, 07:08 PM
I should also add that a short chain is not required. I would never use a chain that won't wrap the big/big. Depending on the exact B screw position, a 54 inch chain may work, but it fully extends the cage, risking damage. The longer chain is quieter.

I'm using a 55 inch chain with short 406mm chain stays. I also use a 48/32 chorus crank, so I have a 42T wrap with a RD that is made to handle a 39T wrap. As you would expect, the 13T is the smallest useable sprocket with the 32T little ring.

I'm not sure what good pictures are, unless you think I'm making this up, but I'll add something to my album.

dbnm
09-16-2020, 07:37 PM
Definitely don't think you are making this up. Just was wondering if a photo would help explain this.

No big deal.

Thanks for the details.

lexlion
09-16-2020, 08:03 PM
Does that mean the Red RD would work?

Dave
09-16-2020, 08:15 PM
Does that mean the Red RD would work?

If it works with a 10-33, it should work with the 10-36, but obviously, 1 inch more chain length is needed. As with the force RD, the B screw may work, but it may need to be changed to a 25mm length.


https://forums.thepaceline.net/showthread.php?t=255165

Dave
09-17-2020, 03:40 PM
Here's a couple of picture of my bike with the standard SRAM Force AXS RD. I wanted to revisit the chain length issue, so I changed the chain back to a 54 inch, which is the same length needed to run a Campy 11-34 with the new Chorus 12 RD, and 406mm chain stays. The chain is long enough, but not as quiet as the 55 inch length. I've shown the bike shifted to the big/big.

The second photo shows the bike in the big/big with the 55 inch chain. Only the 13T and larger sprockets are useable with this chain length when in the little ring.

Notice anything different with the chorus crank?

https://forums.thepaceline.net/picture.php?albumid=93&pictureid=703

https://forums.thepaceline.net/picture.php?albumid=93&pictureid=702

I rode the bike with the shorter chain again and I now think it's the winner. Even in the big/big, there's plenty of swing left to the RD cage. I never intentionally ride the big/big, so I like the fact that the chain never hangs loose in the 32/11. I've exceeded the normal 36T wrap at both ends and had no problem.

The chorus crank has no lettering on it. About 30 seconds of wet sanding with 2000 grit removed the lettering and about 1 minute of polishing brought back the shine.

FlashUNC
09-17-2020, 03:45 PM
This came up here before so I just wanted to post a little additional info.

The regular Force AXS rear derailleur will work with the wide (10-36) cassette.

See here
https://blog.3t.bike/2020/05/14290/sram-force-axs-wide-gearing-hacks-gravel-bike-tech/

I think I am going to try this out.

I would not be comfortable with my RD looking that in big big on a gravel trail.

Sure, it might work in the stand, but SRAM has their guidelines for a reason.

Dave
09-17-2020, 03:55 PM
I would not be comfortable with my RD looking that in big big on a gravel trail.

Sure, it might work in the stand, but SRAM has their guidelines for a reason.

Looking like what? The tighter 54 inch or the looser 55? This isn't a gravel bike, but the shorter 54 inch would meet the big/big plus one inch requirement.

Even with the shorter length it will wrap 41 of the 42 tooth wrap. Sram doesn't allow the little/little combination.

FWIW, the RD will look the same in the big ring and 32T with the shorter chain, as the second pic with the big ring and 36T.

All other combos are looser.

FlashUNC
09-17-2020, 04:02 PM
Looking like what? The tighter 54 inch or the looser 55? This isn't a gravel bike, but the shorter 54 inch would meet the big/big plus one inch requirement.

Even with the shorter length it will wrap 41 of the 42 tooth wrap. Sram doesn't allow the little/little combination.

FWIW, the RD will look the same in the big ring and 32T with the shorter chain, as the second pic with the big ring and 36T.

All other combos are looser.

I was referring to the blog post, not your photos.

R3awak3n
09-17-2020, 06:31 PM
I agree. Blog post does not look good but they mentioned chain was broken to 33t cassette so it makes sense.

Daves colnago on second picture looks fine.