Low gears for SRAM AXS - 675% range

Dave · #1 10-13-2023, 08:27 AM

This year was the first where some of the 12-13% grades that I ride have become dreadful. Rather than avoid them or get an e-bike, I'm experimenting with different methods to get at least a little lower gearing. I already use a 46/30 crank with 10-36 cassette so I can pedal seated through these climbs. Flatlanders can't even imagine why a 30/36 gear ratio would ever be needed.

One method that I haven't tried yet is a chain ring swap to a 44/28. I have new rings from Specialties TA that fit my Shimano GRX cranks on order, but whether they'll work with an AXS chain and shift well is unknown.

I recently installed a SRAM 10-44 1X cassette on my bike and a Wolf Tooth road link to add clearance between the upper jockey pulley and the 44. This actually worked, so I had a little lower 30/38 and an extremely low 30/44 ratio. The lowest allows 4.3 mph at 80 rpm. The RD only has about 40-42T wrap capacity, so sprockets 17 and smaller aren't usable. Fortunately, there's a sequential shift mode that doesn't allow the big/big to be used and also blocks the use of the smallest four sprockets. With that mode, any SRAM AXS 2X RD will work. The chain length is set with the chain length formula to only wrap up to the 46/38. On my bike, it's the same that length that I've been using.

If full use of all sprockets is desired, there's also an aftermarket RD cage available from Cycles Chinook that increases the wrap capacity to 50T. The stock RD cage is 70mm long, while the new one is 93mm. I've got one to try, but had to order the special 4-prong tool to remove the nut holding the cage in place. It's suggested that a chain ring nut tool will work, but it wouldn't work for me. I just hope I didn't damage the nut with the chain ring tool.

https://cycleschinook.com/product/ro...railleur-cage/

ajjr · #2 10-13-2023, 09:46 AM

Rather than swap the cage, you could also try using a SRAM mountain RD to get more usable range on the cassette. 44/28 rings is quite a lot for the RD to take up while still working with a fairly wide casette. I'd also be curious to see how the FD would handle that.

rice rocket · #3 10-13-2023, 09:51 AM

Quote:

Originally Posted by ajjr

Rather than swap the cage, you could also try using a SRAM mountain RD to get more usable range on the cassette.

I think he's looking to stay 2x, SRAM MTB RDs won't wrap much past it's gear capacity anymore since they're all designed for 1x.

Dave · #4 10-13-2023, 10:02 AM

The Rival FD that I'm using works fine, so far. I put a 2 inch longer chain on to shift into the 46/44. It worked, but the chain is really close to rubbing on two protrusions that are formed into the top of the cage. It's not a gear combo that I'd use intentionally. I've been using cranks with 16-17T difference, with Force and Rival FDs for over 3 years now with no chain drops.

Shortsocks · #5 10-13-2023, 10:11 AM

I find SRAM AXS 46/34- 10-36 to be plenty for climbs and keeps me pedaling well on downhills at 40 no problem. Also im Generally in the middle of the cassette in the 46. (But Id like a 48 on flats a lot of the time around here)

tomato coupe · #6 10-13-2023, 10:30 AM

675% for a road bike? Yikes!

ajjr · #7 10-13-2023, 12:20 PM

Quote:

Originally Posted by rice rocket

I think he's looking to stay 2x, SRAM MTB RDs won't wrap much past it's gear capacity anymore since they're all designed for 1x.

Ahh, that's just me speaking about things I don't fully understand. I just assumed that the mountain RD would have more ability to take up slack, so if you used something like a 10-44 with a mountain RD, you would have some excess and could soak up a bigger range up front.

djg21 · #8 10-13-2023, 02:47 PM

Quote:

Originally Posted by ajjr

Rather than swap the cage, you could also try using a SRAM mountain RD to get more usable range on the cassette. 44/28 rings is quite a lot for the RD to take up while still working with a fairly wide casette. I'd also be curious to see how the FD would handle that.

I use an AXS “mullet” with Force shifters, an Eagle AXS RD. I use 1x 44t chainring with 50-10 and 52-10 cassettes on my two wheel sets. All the AXS 12 speed stuff is cross-compatible, and you have a lot of flexibility with the MTB derailleur.

rice rocket · #9 10-13-2023, 02:54 PM

Quote:

Originally Posted by djg21

I uses an AXS “mullet” with Force shifters, an Eagle AXS RD. I use 1x 44t chainring with 50-10 and 52-10 cassettes on my two wheel sets. All the AXS 12 speed stuff is cross-compatible, and you have a lot of flexibility with the MTB derailleur.

e*13 has a 9-52 cassette, even, which equates to 578%.

But Dave is still getting a fair bit more range out of his setup.

Dave · #10 10-13-2023, 04:11 PM

Even my old setup with 46/30 and 10-36 cassette has 552% range. 1X relies on big jumps between sprockets to get more range. The 10-44 deletes the 12 and adds two 6T jumps where the 10-36 has only 4T jumps.

tomato coupe · #11 10-13-2023, 05:01 PM

Quote:

Originally Posted by Dave

Fortunately, there's a sequential shift mode that doesn't allow the big/big to be used and also blocks the use of the smallest four sprockets. With that mode, any SRAM AXS 2X RD will work.

I guess sequential mode is no longer for beginners and dummies, now that you've found a use for it?

Quote:

Originally Posted by Dave

Sram also has sequential and compensating modes that I always discourage. To me they're for beginners and dummies.

Quote:

Originally Posted by Dave

The OP's problem is he wants to do something that the sequential operation mode will not do... It's for beginners who don't know when to shift the FD.

buckfifty · #12 10-13-2023, 05:06 PM

I've seen reports of people successfully running the AXS Xplr rear mech with their wide front mech. I plan on trying it on my gravel bike. 43/30 with a 10-44 in the back

djg21 · #13 10-13-2023, 05:54 PM

Quote:

Originally Posted by Dave

Even my old setup with 46/30 and 10-36 cassette has 552% range. 1X relies on big jumps between sprockets to get more range. The 10-44 deletes the 12 and adds two 6T jumps where the 10-36 has only 4T jumps.

On the road the gaps pose more of an issue. Less so on a gravel bike where cadence tends to be lower, at least for me.

Dave · #14 10-14-2023, 06:38 AM

Quote:

Originally Posted by tomato coupe

I guess sequential mode is no longer for beginners and dummies, now that you've found a use for it?

You put a lot of effort into your rude and worthless commentary, but that's nothing new. If I was a moderator, I'd ban you since you regularly practice nasty posting that does nothing but irritate your victim.

I still don't like sequential mode with any normal use of SRAM AXS drivetrains. The installation of a larger wrap capacity cage will eliminate the need for the sequential mode. It was used a work around for a setup that would never be recommended by SRAM.

Dave · #15 10-14-2023, 09:28 AM

I installed my Cycles Chinook RD cage this morning, along with a chain sized to wrap the 46/44. It works great. I can use all gear ratios from the 30/11 to the 46/44, without using the sequential mode. There's no chain rub on the FD, even in the big/big. No more sequential mode for me!