SRAM AXS Front Derailleur Setup issues.....

[bobones]

My thought is it's the chain. I've had my 2 red axs bikes For over a year. Many chain drops at the start. After some break in with the chain, no chain drops. Installed a new chain recently and back to chain drops. Using red axs chain on red axs chainrings with red axs FD. Replaced chain well before necessary. No issues with wear on chainrings or cassette. So I assume I will be ok again after break in period. It's crap overall though. I read Shimano 12S Was causing FD chain drops as well. Lots of teams at PR using 11S.

It's not the chain, nor the rings. I rotate 2 Red and 3 Force chains on AXS Red and Force chainsets without these issues.

What make/size of frame do you have? Did you set up the FD yourself and have you tried to adjust it to correct the problem?

[woodyvalentine]

My thought is it's the chain. I've had my 2 red axs bikes For over a year. Many chain drops at the start. After some break in with the chain, no chain drops. Installed a new chain recently and back to chain drops. Using red axs chain on red axs chainrings with red axs FD. Replaced chain well before necessary. No issues with wear on chainrings or cassette. So I assume I will be ok again after break in period. It's crap overall though. I read Shimano 12S Was causing FD chain drops as well. Lots of teams at PR using 11S.

It's not the chain, nor the rings. I rotate 2 Red and 3 Force chains on AXS Red and Force chainsets without these issues.

What make/size of frame do you have? Did you set up the FD yourself and have you tried to adjust it to correct the problem?

Cervelo, both size 54, Caledonia 5, and Aspero. I set it myself using the FD tool. Also brought it to a shop at one point and they said it was within spec and didn't change anything.

But as I said above, I only had chain drops for the first month or so when the bike was new, then went away. Was all good for 8 months of riding, changed chain, back to a few drops.

Caledonia is 48/35 x 10/28
Aspero is 46/33 x 10/32

[Matte86]

It happens to me as well.. Sram Red 48-35 / 10-33.. with waxed and non waxed flattop red and force chains..
In October 2020 it started with a KMC dlc 12s chain with Carbon Ti 48-35 rings.. chain dropped 50% of the time.. they said it was the chain non suitable for AXS groups..so I moved to a flattop one.. it didn’t change a lot .. then it appeared there were issues with the carbon Ti AXS inner ring.. I then mounted a V2, the number of chain drops decreased sensibly, but every now and then it happened anyhow.. so I moved to a full AXS crankset, but the frequency of chain drops kept the same .. I then moved to waxing and tried with Red and force chains.. it didn’t change anything.. I brought the bike to 5 different mechanics, but the problem continues.. plus at the same time I had issues of the breaking lever as mentioned in the other (more recent) thread..
Saturday during my ride up a climb, not under load (as I’m non-stop worried about chain drops), it happened twice.. so as enough is enough I moved to DA ( just waiting for the cranks)
IMHO and for my riding overall AXS as strong points as the 48t in the front, the way it shifts (just one lever on each side), cassette range, cleaner installation etc.. but the chain drops are a no go in 2022.
One thing is that AXS front d is more sensible and needs precision, but after all the problems and complaints mentioned here and occurred to my buddies and me riding AXS groups, unfortunately I think there are some flaws in the FD design

[bobones]

OK, there is obviously a very narrow window for setting these up to work correctly, but I believe in the vast majority of cases it can be done by tweaking the cage alignment and limit screws. You only need a couple of hex wrenches and a bike stand, so whatever you do, forget about taking it to somebody else to fix for you.

I'll concede there may be some other factors at play which make perfect front shifting impossible in some cases, but as someone with 4 eTap groupsets, and who has set them up with bad shifting and then been able to correct it on a range of frames, I am convinced that a significant number of other users can correct their setups too.

It may sound patronising, but watch the SRAM tech videos to remind yourself of the recommended process and then start from scratch by removing the chain and realigning the FD. If you've got the FD alignment tool then there's a separate video for that.

The key aspects for me are that the cage should be low and absolutely parallel. Forget about the height adjustment guide line inside the cage (it may be in the wrong place!): just set is as low as it will go and still clear the top of the tallest teeth by 1 mm. When you tighten the FD bolt, make sure that is stays absolutely parallel to the chainrings, and is not toed in or out at all.

When the chain is on, affix the correct wedge, and set the limit screws as per the videos, i.e. chain almost touching outside cage plate in largest gear and inside plate in smallest gear.

Now, this is the bit that isn't in the videos: with the bike in the stand, test the shifting using the button on the FD over a range of cogs on the cassette. You should be able to rapidly execute front shifts all over the cassette without it throwing over the top. Do 10 or more rapidly on each cog at the back to check. If you find a cog where it tends to overthrow (usually near the middle of the cassette), turn the high limit screw to move the cage inboard by a fraction until you can execute rapid front shifts without any overthrows. Again, test the front shifting on different cogs on the stand and then go for a ride.

If you've followed the videos to the letter, done this fine tuning and still get overthrows or bad shifts, try it once more from scratch, then by all means give up, sell your SRAM gear and go buy another groupset. Just don't waste your time expecting anyone else to fix it for you.

[DaveS]

Still blaming the FD when the real problem may be poorly functioning chain rings. I've set up two Campy 48/32 cranks and four grx cranks with no problems. I never use a wedge either. I don't use the sequential or compensating modes. In July I'll have been riding two force equipped bikes for two years with no chain drops.

[bobones]

Still blaming the FD when the real problem may be poorly functioning chain rings. I've set up two Campy 48/32 cranks and four grx cranks with no problems. I never use a wedge either. I don't use the sequential or compensating modes. In July I'll have been riding two force equipped bikes for two years with no chain drops.

You might be right in that the setup with Campag/GRX rings may be more tolerant than native AXS, but I am trying to help people with full AXS setups. I have 3 different AXS chainsets and can set them up to overthrow or not, so unless SRAM have some serious manufacturing tolerance issues (which they might well do), I still believe suboptimal setup is the primary reason for drops. IME 11-speed eTap was/is much worse for drops, and I definitely had better results when I swapped to a KMC chain and Praxis rings, but I don't see this with AXS on the gear I have, and I can move stuff about from one bike frame to another and consistently set it up to have good front shifting with the technique I posted.

[gSporco]

Theres a lot at play here as Ive mentioned before (above), Could very well be frame angles. geometry, could be Sram Chain rings..

My latest theory is the over throw or over shift that the FD does going up or down.. If you watch it, by design it moves the FD further than the limit to make sure the chain goes up or down.. Its is possible that some FD over throw tolerances are off and literally over throws the chain before it snaps back to its limit.. This would explain why such a tight tolerance is necessary for proper functionality.. Think about it, if you are off by 1mm and the over throw is 1 or 2mm.. You can be throwing the chain almost 3mm to far in either direction..

This could have been fixed with firmware or newer units shipping.. For example, my last run with AXS was with the newer Rival AXS and that FD never dropped a chain, and I did notice the overthrow wasnt as aggressive as when I last setup a Force AXS FD from 2020..

Who knows, we can added to the list of what ifs..

[tomato]

Still blaming the FD when the real problem may be poorly functioning chain rings.

You've blamed everything except the front derailleur - chain rings, crank sets, shifting under load, sequential shifting mode, incompetent users, incompetent shop mechanics, etc. If a front derailleur doesn't work properly with the chain rings it was designed to work with, it is still a poorly designed derailleur.

[bobones]

Theres a lot at play here as Ive mentioned before (above), Could very well be frame angles. geometry, could be Sram Chain rings..

My latest theory is the over throw or over shift that the FD does going up or down.. If you watch it, by design it moves the FD further than the limit to make sure the chain goes up or down.. Its is possible that some FD over throw tolerances are off and literally over throws the chain before it snaps back to its limit.. This would explain why such a tight tolerance is necessary for proper functionality.. Think about it, if you are off by 1mm and the over throw is 1 or 2mm.. You can be throwing the chain almost 3mm to far in either direction..

This could have been fixed with firmware or newer units shipping.. For example, my last run with AXS was with the newer Rival AXS and that FD never dropped a chain, and I did notice the overthrow wasnt as aggressive as when I last setup a Force AXS FD from 2020..

Who knows, we can added to the list of what ifs..

There are definitely the occasional rogue shifts where either the cage moves too much or too aggressively or the chainring ramps are too effective at moving the chain up. It could be the FD itself or something in the timing of chain in relation to the chainrings or some other factor. Whatever the case, it's definitely far too sensitive to misalignment and the window for correct setup is far too small. In some situations it may be impossible to stop the overshifts without preventing front shifting working at all. I accept that. However, the whole point of the fine tuning technique I posted is too look for these rogue shifts and try to negate or minimise them by having the cage move only as far as it needs to and no more. If you get overshifts on the stand you are doomed to get them on the road, so you need to try to find them and adjust them away if you can. The best starting point for that IME is to adhere to the SRAM instructions and take it from there. If you've done all that and still have problems then bin the AXS stuff altogether or get a Campag or GRX crank!

[DaveS]

Still blaming the FD when the real problem may be poorly functioning chain rings.

You've blamed everything except the front derailleur - chain rings, crank sets, shifting under load, sequential shifting mode, incompetent users, incompetent shop mechanics, etc. If a front derailleur doesn't work properly with the chain rings it was designed to work with, it is still a poorly designed derailleur.

There are plenty of users who have no shifting problems with their AXS cranks, so your logic seems flawed. All you hear about is from those with problems and the comments lean heavily toward people who can't do their own work and neither can the shops where they take their bikes. Its a simple setup.

[tomato]

Still blaming the FD when the real problem may be poorly functioning chain rings.

You've blamed everything except the front derailleur - chain rings, crank sets, shifting under load, sequential shifting mode, incompetent users, incompetent shop mechanics, etc. If a front derailleur doesn't work properly with the chain rings it was designed to work with, it is still a poorly designed derailleur.

There are plenty of users who have no shifting problems with their AXS cranks, so your logic seems flawed. All you hear about is from those with problems and the comments lean heavily toward people who can't do their own work and neither can the shops where they take their bikes. Its a simple setup.

I didn't blame the chain rings, you did. And, now you're blaming end users and bike shop mechanics again.

The bottom line is SRAM seems to have more problems with front derailleur setup than Shimano or Campy. Your "blame the owners and the shop mechanics" approach requires that either SRAM owners are less mechanically inclined than Shimano and Campy owners, or SRAM owners are more likely than Shimano and Campy owners to take their bikes to incompetent mechanics. Neither idea holds water.

[Nickldn]

Still blaming the FD when the real problem may be poorly functioning chain rings.

You've blamed everything except the front derailleur - chain rings, crank sets, shifting under load, sequential shifting mode, incompetent users, incompetent shop mechanics, etc. If a front derailleur doesn't work properly with the chain rings it was designed to work with, it is still a poorly designed derailleur.

There are plenty of users who have no shifting problems with their AXS cranks, so your logic seems flawed. All you hear about is from those with problems and the comments lean heavily toward people who can't do their own work and neither can the shops where they take their bikes. Its a simple setup.

I didn't blame the chain rings, you did. And, now you're blaming end users and bike shop mechanics again.

The bottom line is SRAM seems to have more problems with front derailleur setup than Shimano or Campy. Your "blame the owners and the shop mechanics" approach requires that either SRAM owners are less mechanically inclined than Shimano and Campy owners, or SRAM owners are more likely than Shimano and Campy owners to take their bikes to incompetent mechanics. Neither idea holds water.

I can tell you that my Campy Chorus 12 FD was a PITA to set up. Compared to a Shimano Ultegra 6800 FD it's definitely ultra sensitive to set up.

I will say the Campy 12s FD is less of a PITA than the Red Etap 11s FD for chain drops though, but not by that much.

So my theory is that thinner chain = less margin for error, even from the established manufacturers. Chatter about Shimano 12s chain drops seem to support this theory too.

[DaveS]

Still blaming the FD when the real problem may be poorly functioning chain rings.

You've blamed everything except the front derailleur - chain rings, crank sets, shifting under load, sequential shifting mode, incompetent users, incompetent shop mechanics, etc. If a front derailleur doesn't work properly with the chain rings it was designed to work with, it is still a poorly designed derailleur.

There are plenty of users who have no shifting problems with their AXS cranks, so your logic seems flawed. All you hear about is from those with problems and the comments lean heavily toward people who can't do their own work and neither can the shops where they take their bikes. Its a simple setup.

I didn't blame the chain rings, you did. And, now you're blaming end users and bike shop mechanics again.

The bottom line is SRAM seems to have more problems with front derailleur setup than Shimano or Campy. Your "blame the owners and the shop mechanics" approach requires that either SRAM owners are less mechanically inclined than Shimano and Campy owners, or SRAM owners are more likely than Shimano and Campy owners to take their bikes to incompetent mechanics. Neither idea holds water.

You don't know what or if there's any specific problem and neither do I. I've only suggested trying different cranks to see if the problem goes away. If cranks that I know work properly don't cure chain drops, I'd have to say that FD setup isn't being done properly. I've done many setups and never had problems. I've used 6 different cranks that all worked perfectly.

[tomato]

You've blamed everything except the front derailleur - chain rings, crank sets, shifting under load, sequential shifting mode, incompetent users, incompetent shop mechanics, etc. If a front derailleur doesn't work properly with the chain rings it was designed to work with, it is still a poorly designed derailleur.

There are plenty of users who have no shifting problems with their AXS cranks, so your logic seems flawed. All you hear about is from those with problems and the comments lean heavily toward people who can't do their own work and neither can the shops where they take their bikes. Its a simple setup.

I didn't blame the chain rings, you did. And, now you're blaming end users and bike shop mechanics again.

The bottom line is SRAM seems to have more problems with front derailleur setup than Shimano or Campy. Your "blame the owners and the shop mechanics" approach requires that either SRAM owners are less mechanically inclined than Shimano and Campy owners, or SRAM owners are more likely than Shimano and Campy owners to take their bikes to incompetent mechanics. Neither idea holds water.

You don't know what or if there's any specific problem and neither do I. I've only suggested trying different cranks to see if the problem goes away. If cranks that I know work properly don't cure chain drops, I'd have to say that FD setup isn't being done properly. I've done many setups and never had problems. I've used 6 different cranks that all worked perfectly.

How many bikes is that? I'm guessing one model, maybe two.

[raggedtrousers]

As I said earlier, the simplest explanation here is that some FDs are faulty. That would explain, with 1 variable, not only the drops, but why some people have no issues, while others cannot resolve the problem. Also as stated before, for those who have had no difficulties to assume that all those who have are mechanically inept, as are all the mechanics they have enlisted to help, is illogical and (however well intentioned) a bit patronising.