Maybe you just need a cable...

just joking.

 

I'm sure you can find a bunch of these posts on this site and other sites as well. My bike has suffered from it badly since putting one on, but l really like the convenience of electronic shifting so I'lll keep using them until the backup that I have is toast too. After that, I might just go back to mechanical because the amount of chainslap on my bike is insanely annoying. They might as well not even put a clutch on these things during manufacturing.

 

Glad to hear it’s not just me. I have buddies running X01 axs who don’t have this issue so may be specific to GX. I’m on the same page as you. Looking to go back to mechanical soon here. Tried it out of curiosity, work at a shop and like to have opinions on a variety of products. Safe to say you’ll see me on mechanical GX again soon

 

I also have this issue. I wonder if the clutch is different between the GX and X01/XX1 derailleurs. I'd really like to figure out what's causing it cause it drives me nuts.

 

Have a friend who run the X01 axs and said it was still very loud. Have other friends running GX AXS who say it’s dead silent. Really unsure what the issue is, may reach out to SRAM

 

If you have access to both derailleurs (GX and X01/XX1), it would prolly easy enough to setup a quick method to calculate the differences. If so inclined.

 

I have to say, I’m pretty impressed with how quiet and smooth my XX1 is.

 

I bet it has nothing to do with axs.
B nut adjustment. Upper jockey wheel too close to cassette?

 

It’s not the B screw. I’ve backed off all the limits and had other techs set it up just in case they do something different - always slaps.

 

I didn't notice the chain slap on my Yeti SB150 or Revel Rascal, but it's now on a Propain Hugene and the "clunk" on chunkier descents is now noticeable and pretty annoying. It's only an issue on faster/rockier stuff so it's hard to consider going back to cable because I like it so much other than this one problem. I've read/heard the clutch is the same for all AXS derailleurs and that it's the same as with non-AXS derailleurs, but I don't think it's the clutch because the noise isn't chain slap, it's more of a clunk. I suspect SRAM didn't factor in the extra weight of the battery and the whole assembly is pivoting around on harsher stuff. It's just a theory, though.

 

The issue is not the clutch. Because axs is wireless you no longer have the shifter cable tension. The cable does not allow the derailleur to pivot from the hanger. I saw an article on the issue comparing wireless to wired. The wireless swings at the hanger pivot point creating chain slap. There are a few hacks using rubber grommets or o rings if you can find one that fits.

 

Any short advice where to put the rubber or the o ring? Didnt find anything yet on the net

 

Well, I can tell you on the descent that it is super clunky and chain slapping everywhere. Don't know about everyone else but I like my carbon frame, I will say that the shifting is spot on - man I love it - however.... tear up my frame? Going back old school, until SRAM gets this issue fixed for the mountain bike riders - well old school it is!

 

^^^^
Perhaps you could just protect your chain stay and go ride

 

Has anyone found any solutions to this?

 

new stumpy carbon eve one week in paint removed from chain stay . Thanks SRAM 😢

 

^^^^
Say what?

 

I have the same issue. I got the Stumpy 15 Expert and I just took it in for its first service. I told them about the clunk/clack sound and even showed them a video (I was filming some of my rides with chest mount action cam). They have had a really thorough look at it and compared with some other bikes that also have the GX AXS T-Type and they all have really bad chain slap which is where the noise is coming from (they filmed in slow-mo with someone doing bunny hops and confirmed it is the chain slapping). I'm pretty pissed. This bike is awesome and so quiet but as soon as I get on some slightly chunky terrain is clack clack clack the whole time. They happened to have a SRAM XX cage that was lightly used off another bike that they put on to see if it would fix the problem (it's lighter because it uses some titanium instead of steel) and they said it's better but still not fixed. I would be happy-ish if they were doing this fix for free but they want to charge me for this. The GX derailleur is faulty man. This is not acceptable for a derailleur that costs so much money but causes chain slap on a $12k NZD bike. This is not cool. I wonder if we get enough people complaining to SRAM if they will do a recall or provide some sort of fix.

Here's one of my videos. If you skip to 50 seconds you can hear it clacking on every bump.

UPDATE: I went to speak to them at lunch and said I don't want the new derailleur cage coz I don't want to spend more money on a problem that shouldn't even existing on a brand new Specialized. They said they would talk to Specialized and actually found that my bike has an early model chain stay protector and the newer ones have a lot more pronounced ridges on them so they are going to swap out my chain stay protector with the one that is on the other Stumpy 15 in their shop and we will see if that fixes/helps the problem. Fingers crossed. I'll pick it up after work. It's not the end of the world, it's just a clunking sound but the bike is otherwise so quiet and pleasant and fantastic to ride so it's kind of just a turd in the soup when it clunks down over every root, rock and drop.

Update #2: The different chainstay protector didn't fix anything so it's either a bad design on the chainstay protector or a bad design on the clutch of the mech or more likely a combination of the two. They are going to fit some STFU chain guides free of charge. I'm not a fan of the look of them but I'm sure they will work well to stop the noise.

 

This little washer/shim really helped quiet down my AXS derailleur, on both bikes. Worth a shot for a few bucks!

Super Shims – Madrone Cycles

 

It's still at the shop. They didn't want to send me away without a fix so they said they will order in some of those STFU chain guides and fit them which they did earlier today but it didn't fix the issue. Now they think that it is actually hitting the cage of the derailleur. The guy said he will talk to his boss and see if they can swap my derailleur with a demo bike that has the same derailleur to see if that fixes the issue and they will send mine away to get checked out. It sounds like the GX AXS T-Type derailleurs just have insufficient damping on their clutch, or maybe it's just my one. I left it with them since the weather is atrocious right now so I can't ride anyway and I also have an e-bike that I can ride in the mean time. I'll wait and see what they come up with. Sounds to me like either a faulty derailleur or a really bad design by SRAM.

Edit: I had a look at that link you sent but they don't show T-type in the listing. Will this work on T-Type?

 

Update: They still have the bike. The STFU chain guides didn't do anything. After trying this and realising it made no difference they thought it might be the sound of the chain hitting the derailleur cage but now they think it might be the chain hitting the underside of the chainstay? They have been using slowmo video to try to see what the chain is doing when they bunny hop it. So they have ordered a chain guide or guard, I couldn't quite understand what he said on the phone. These guys are really putting a lot of effort in to try to solve this problem for me so I'm pretty grateful for that. Hopefully this solution will stop the sound or at least dull it down a bit. I'll know in 2 days when I pick it up. Nobody else has a Stumpy 15 that can comment if they have the same clacking sound when going down rough terrain? The bike is super silent until I hit gnarly terrain or drops and then I can hear the chain hitting something.

 

I have a new Stumpjumper 15 with XO t_type and on rough terrain it's miserable. Have talked to SRAM and they gave a whole spell about how good their clutch is and nothing is wrong. It was bad enough I had my first derailleur warrantied and second one is just as bad. Specialized says they heard of the issue and said to check with my shop about a frame issue. Even sent my shock to Fox to confirm it was OK. Bike is awesome otherwise but I'm not sure I can live the clunking and chain rattle. I coasted some downhill trails with no chain or derailleur and the issues were gone. My shop thinks I need to spend a bunch of time trying different shock settings repeating a section of trail over and over changing one thing at a time but I know my tire pressures and shock settings are good. 99.9% that won't solve anything. It's a shitty derailleur. Simple as that. They way the shock uses a lot of travel easily may contribute to the issue as well.

 

Damn bro that sucks!! Tell your shop to talk to Specialized because they must be getting a lot of complaints from people about this. My bike is still at the shop. They tried fitting a chain guide and there's no improvement. They are waiting for Specialized to tell them what to do next. Out of interest, what size is your bike/frame? Mines an S5 and the shop said that the S4 and lower hasn't had any issues but the S5 has a longer chainstay so maybe it's something to do with that? They are still looking at the way that the chain slaps onto the chainstay but I don't think that is the issue. It's fully coated in rubber so if the chain hit that it would just be a dull thud not a clack sound. I reckon it must be the sound of the chain hitting the derailleur cage or something like that. And this might be worsened by the derailleur clutch not being strong enough or something like that. They have tried a lighter cage, and it made almost no difference. Hopefully Specialized will come up with a proper solution to the problem because I am guessing there are thousands of people out there with the same issue.

 

Dang! I have a S5 too. Glad to hear it's not just me. SRAM and Specialized admit nothing and act like it's just me. My shop also thinks I'm a bit nuts for how many times I've been in there and complaining about my bike. I'm sure suspension adjustments are not it. I'm on a Facebook Transmission group and few guys have said the Stumpy is noisier than most with T-type. Another guy mentions suspension design and the way the Genie works. I talked to an old friend again last night who lives in another state and is a great bike mechanic and we hashed out a bunch of ideas and came up with this to try: Use the setup cog 7 and 118 chain length. I have a 32 front ring. Set up calculator for an unknown bike with 445 chain stays says position A and setup under SAG. So I'm going to partway start over on setup. Micro adjust to middle (7). put chain in small cog lock out cage and take back wheel off. Change from B to A and put derailleur in setup mode, loosen derailleur and shift 5 times to gear 7. Put wheel back on. Leave axle and derailleur a little loose. Go to shop or have someone help you with this. Sit on the bike and have the other person pull back the derailed and tighten everything under sag. A few guys on Facebook mentioned doing it under too. After living with this and trying every other thing, this might be it? Excited to try it today. What we worked out last night is that with the longer stays, like you said and shock motion when you you have it set up how the instructions say it's not enough tension. When you are on the bike compressing it weighted going through rough terrain the tension on the chain becomes way too little. Setting it up under sag may compensate for that. I think this might do it. It makes a lot of sense to me. I'll know in the next day or 2 and post my findings.

 

Damn bro I'm sorry to hear that your shop is not playing ball! I look forward to hearing your findings. It sounds promising! Also if it doesn't fix it, try to get some videos of the issue. My bike shop looked at the bike for me but then kinda brushed it off initially but when I said I had a video of the sound they straight away started taking it a lot more seriously. Not saying that they were not being helpful because they were, very good guys at this shop, but when they heard the sound in the video they straight away were like "Nah that's not right. It shouldn't be making that sound." and since then they have spent a lot of time trying different things and liaising with Specialized so the video definitely helped to escalate the response.

 

I reset my bike up but left derailleur and axle loose and went to my shop. After explaining everything and what/why I want to try in under sag he had a light bulb go off and gets it now. He's on board to solve this too. I think I'm the first one with an S5. They mostly sell S3 & S4 sizes and hear no complaints. I'm riding later today and I'll see how it goes.

 

I got a ride in on some not so rough trails and my above setup changes improved it a little but it didn't solve the issue. I'm going to ride something much rougher tomorrow morning to get a second try on this setup. I'm now curious how S4 seat and chain stays would be on my S5?

 

I rode again this morning and it was almost as bad as before. I took a video for sound to show my shop guy. I think he will ride it tomorrow to see for himself.

 

Any update on this? I love my Stumpjumper but I am getting a bit fed up with the clunking. It definitely sounds like it’s coming from the derailleur.

 

My shop guy rebuilt my rear hub with lighter grease and that helped a tiny bit but didn’t solve it. I’m pretty sure it’s the derailleur too. It’s winter here and hard to try things now but I’m going to try a different shock I have to see how that affects the back end movement. Curious if that would change the derailleur clunking? I also want to try shorting the chain a little. If those do nothing I will put my XT drivetrain on and tape the cable to frame and try that. I really like my Stumpjumper too but am also sick of the clunking sounds.

 

My shop guy rebuilt my rear hub with lighter grease and that helped a tiny bit but didn’t solve it. I’m pretty sure it’s the derailleur too. It’s winter here and hard to try things now but I’m going to try a different shock I have to see how that affects the back end movement. Curious if that would change the derailleur clunking? I also want to try shorting the chain a little. If those do nothing I will put my XT drivetrain on and tape the cable to frame and try that. I really like my Stumpjumper too but am also sick of the clunking sounds.

 

Damn I was hoping my you had a fix haha. Honestly I don’t think switching out shocks is going to do much. I have tried running the genie shock with 1 (stock), 2 and 3 spacers and with the it’s way firmer than with 1 and it still clunked as much, if not more than the stock setup. The derailleur is unsprung so I don’t think it’s really affected by the suspension at all. There is pedal kick back and stuff like that but that has a very different, higher pitched sound. When I pull the derailleur cage all the way forward and release it it makes a similar clunking sound so I’m 90% sure it’s just a badly designed derailleur or faulty derailleur. When I take it in for its next service I will get them to check the derailleur. They had previously said that they could send it away to have it checked by SRAM.