SRAM chain: has this happened to you?

[Nick12]

Went out for an easy ride today and as I started going uphill I dropped into the front chainring. Didn’t think I was pushing that hard, but I must have been as the chain bent. Like, it’s twisted. Never seen this before, have you?







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[Spinner]

Last year, I had a 9-speed DA chain twisted like that while making a similar shift (I had changed the crankset and the front derailleur was not yet set-up perfectly). I replaced it with a 9-speed Record chain (used lightly) and was blown away by improved shifting and reduced noise.

[Dave]

SRAM AXS FDs get blamed for shifting problems that I suspect are really caused by poorly functioning shift ramps. When I first made the switch on two rim brake bikes, I kept my Campy chorus 48/32 cranks and they worked perfectly. Before that I was already using the AXS chain with the rest Campy. I later switched to Shimano GRX 46/30 cranks for lower gearing. Those also shift great, but I do use 2mm spacing washers to correct the chain line.

I often start a climb pedaling standing, then sit and quickly shift to the little ring so no compensating shifts are required. I would never use the sequential mode because an attempt to shift into the next to largest sprocket will cause a shift to the little ring, followed by 1 or 2 sprocket shift to a smaller sprocket. Do that while standing and the results could be ugly.

I've logged over 15,000 miles with Force AXS chains and never had a chain drop or otherwise failed chain ring shift. I've also never found the FD to be difficult to set up. I've done it at least a dozen times with three FDs and seven different cranks.

I've put a dozen AXS chains into use and never had any problems. I alternate chains among three bikes that all use the same 55 inch chain length, so there are 10 in the queue. Two are 54 inch and can only be used with a 10-33 or smaller cassette.

[madsciencenow]

Originally Posted by Dave

SRAM AXS FDs get blamed for shifting problems that I suspect are really caused by poorly functioning shift ramps. When I first made the switch on two rim brake bikes, I kept my Campy chorus 48/32 cranks and they worked perfectly. Before that I was already using the AXS chain with the rest Campy. I later switched to Shimano GRX 46/30 cranks for lower gearing. Those also shift great, but I do use 2mm spacing washers to correct the chain line.

I often start a climb pedaling standing, then sit and quickly shift to the little ring so no compensating shifts are required. I would never use the sequential mode because an attempt to shift into the next to largest sprocket will cause a shift to the little ring, followed by 1 or 2 sprocket shift to a smaller sprocket. Do that while standing and the results could be ugly.

I've logged over 15,000 miles with Force AXS chains and never had a chain drop or otherwise failed chain ring shift. I've also never found the FD to be difficult to set up. I've done it at least a dozen times with three FDs and seven different cranks.

I've put a dozen AXS chains into use and never had any problems. I alternate chains among three bikes that all use the same 55 inch chain length, so there are 10 in the queue. Two are 54 inch and can only be used with a 10-33 or smaller cassette.

With etap I never had issues on the FD set-up (if memory serves I used a couple different cranks, DA, Ultegra and SRAM) but with my one AXS Force 2x set-up I've had nothing but issues. The FD doesn't move the chain smoothly shifting to the small chain ring (it does it in two movements and it doesn't fully drop on the first movement so there is a delay or it drops the chain completely). I'm interested in your protocol for setting up the FD. I've followed the instructions and used all the the plastic tools provided and I'm still having issues. Any tips or tricks you've stumbled upon are appreciated.

[Kyle h]

Originally Posted by madsciencenow

With etap I never had issues on the FD set-up (if memory serves I used a couple different cranks, DA, Ultegra and SRAM) but with my one AXS Force 2x set-up I've had nothing but issues. The FD doesn't move the chain smoothly shifting to the small chain ring (it does it in two movements and it doesn't fully drop on the first movement so there is a delay or it drops the chain completely). I'm interested in your protocol for setting up the FD. I've followed the instructions and used all the the plastic tools provided and I'm still having issues. Any tips or tricks you've stumbled upon are appreciated.

This was my experience as well. I had multiple shops try and set up my AXS FD when I had my sl6 setup with AXS and it was almost like clockwork that at 300mi it would somehow become misaligned and start dropping. I’m I spent significantly more time trying to solve my FD issues than I saved by not having to run a di2 wire…

[dustyrider]

Dang Dave. Do you run a race team or something? That’s a lot of chains. I get the crankset chase, I’m still on it for one my bikes myself.

I have nothing to add since my last experience with sram was x9 mtb and I always ran a shimano front derailleur back then. It’s nice to know somethings never change.

[Dave]

The most common problem with the AXS FD is failing to verify that the alignment marks are parallel to the big ring, after the clamp bolt is fully tightened. Mine all swing the tail to the outside, so I angle the marks inward a little and watch the marks move as the bolt is tightened. The marks only have to be parallel, not directly over the teeth. The side to side position is set with the limit screws, after the chain is installed. I've never found the limit screw position or height to be all that critical either. I never use a wedge or a chain catcher.

The plastic tool may help to set the height, but it does nothing to keep the FD from twisting.

I'd get rid of your SRAM crank first. Unfortunately, there aren't many to choose from.

[Dave]

Originally Posted by dustyrider

Dang Dave. Do you run a race team or something? That’s a lot of chains. I get the crankset chase, I’m still on it for one my bikes myself.

I have nothing to add since my last experience with sram was x9 mtb and I always ran a shimano front derailleur back then. It’s nice to know somethings never change.

With three bikes, the idea is to have enough chains for the life of the cassettes. The chains get rotated every 600-1000 miles for cleaning. The chains are hung doubled over on a long bolt. Cleaned chains go at the back and chains for installation come off the front.

[tomato coupe]

Originally Posted by Nick12

Went out for an easy ride today and as I started going uphill I dropped into the front chainring. Didn’t think I was pushing that hard, but I must have been as the chain bent. Like, it’s twisted. Never seen this before, have you?

Wow, that's something you don't see often (ever?)

[Nick12]

The problems keep mounting. Took the chain off and the frame is cracked. Very frustrating this. Never knew a dropped chain can cause so much damage.

I had the LBS set up the FD as I’ve heard it’s notoriously problematic. Haven’t been riding much so was excited to be finally getting out. Gonna be a few weeks before I can get this sorted.







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[catchourbreath]

Where's the crack? Looks like mostly paint. Those FDs aren't bad if you use the alignment tool and read the directions. Similar to the R8000 FD that nobody read directions for and they were (and often still are) set up wrong.

Chain twisted like that I've only seen from getting jammed and being near cross-chained or just moving a bit of cadence.

[Nick12]

Originally Posted by catchourbreath

Where's the crack? Looks like mostly paint. Those FDs aren't bad if you use the alignment tool and read the directions. Similar to the R8000 FD that nobody read directions for and they were (and often still are) set up wrong.

Chain twisted like that I've only seen from getting jammed and being near cross-chained or just moving a bit of cadence.

There isn’t a hole but the carbon is damaged. Not sure if this angle shows it better.



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[pasadena]

Damaged but repairable on the carbon. You can look at getting a metal plate protector- they sell them aftermarket that stick onto that area for this reason.

SRAM is garbage with road components. Don't know why. The mtb stuff is pretty decent.

[Dave]

I'd limit my criticism of SRAM road parts to their cranks. All other parts that I have work perfectly.

[yinzerniner]

Originally Posted by Dave

The most common problem with the AXS FD is failing to verify that the alignment marks are parallel to the big ring, after the clamp bolt is fully tightened. Mine all swing the tail to the outside, so I angle the marks inward a little and watch the marks move as the bolt is tightened. The marks only have to be parallel, not directly over the teeth. The side to side position is set with the limit screws, after the chain is installed. I've never found the limit screw position or height to be all that critical either. I never use a wedge or a chain catcher.

The plastic tool may help to set the height, but it does nothing to keep the FD from twisting.

I'd get rid of your SRAM crank first. Unfortunately, there aren't many to choose from.

Dave seems to be the axs FD magician, but to us mere mortals without the Midas touch the setup and continued operation was initially way more problematic

However my experiences are similar to his but the diagnosis and remedy are slightly different.

As an early adopter of Red AXS on my precious Open UPPER I had the chain drop problems as well, which ended up causing worse chainstay damage than the OP (chainsaws are effective for a reason). I had 11s etap and never had any issues with chain drip, but with red axs I had a chain drop every 3-400 miles. Setup was done perfectly with alignment and wedges but would somehow work its way loose.

However since they released the alignment tool the drops have basically been eliminated. My theory is similar to what Dave mentioned - when axs was first released they didn’t have the wedge tool and the FD was floating/unsecured before final tightening. And during the final install of wedges and tightening of bolts there’s just enough minuscule amounts of play that the alignment goes a tiny bit off, and over time it drifts just enough to cause drop issues. However with that tool, since you tighten everything from a secured start point there’s no movement, and any tiny amounts of play/drift later on is small enough to not induce drops.

With the tool even pretty drastic chainline and chainring alteration keeps the front shifting quality. Using one piece RED AxS 46/33 and two piece Force AXS 43/30 rings, regular and wide FDs, and 45mm (regular) 47.5mm (wide) and 49mm (mtb) crankarms, all worked fine great when setup with the tool.

As for the chain bending like that, seems much more likely on the flat top vs other chains due to the outer plate thickness or lack thereof. While the plate is taller to help resist stretch/deformation from the normal pulling load of pedaling, the thinning makes it more susceptible to deformation from twisting.