[BrandNoobian]

Hi all,

Sort of at my wits' end here. New to mountain biking and, while I'm green as can be, I love every aspect of it. I've had my bike for about 6 weeks and about two weeks ago, I had a fluke mechanical failure where my SRAM XX1 chain slipped of mid-stroke and got jammed into the cage plate of my GX Eagle derailleur (with the AXS kit). It twisted the cage plate three ways and bent the pulley. LBS recommended replacement of the derailleur and I agreed wholeheartedly.

I put on the GX AXS derailleur and on my first long ride, intermittently, when I would stop pedaling and then pedal again, it would seem like the chain was skipping and not creating torque right away. No shifting involved and the chain was never skipping gears. I haven't gone back to the LBS yet because I'm a little frustrated with them at the moment. I took a video of the derailleur while cranking the bike on my stand. The derailleur seems to flutter and I have no idea if this is normal or not? If it is, any thoughts on what could be causing this "chain skipping" sensation when I pedal? My YouTube University education is suggesting a host of things it could be but I'm wondering if the hanger was bent after the first derailleur issue. I've attached a photo showing the bent cage arm (above) and pulley from the first incident and a link to a video of the "flutter" I'm experiencing currently Any suggestions is greatly appreciated!

 

[J.B. Weld]

It's hard to tell exactly from the vid. Pedaling slower, a shot from behind, and a few shifting sequences would help. For sure a misaligned hanger or something else could be contributing but it seems like it may also just be a simple adjustment.

Not understanding your frustration with the shop, didn't you say that you installed the derailleur? Inquiring minds want to know

 

[BrandNoobian]

It's hard to tell exactly from the vid. Pedaling slower, a shot from behind, and a few shifting sequences would help. For sure a misaligned hanger or something else could be contributing but it seems like it may also just be a simple adjustment.

Not understanding your frustration with the shop, didn't you say that you installed the derailleur? Inquiring minds want to know

My frustration with the shop is they replaced the derailleur and said everything was working as it should. This issue popped up on my first ride and is easy to replicate (my neighbor, avid mountain biker, rode it around the block and experienced the issue). Seems like the shop didn't bother to check their work or I don't have the right expectations for what the replacement of the derailleur should include. Additionally, I reached out to the shop on Saturday, 6 days after I was there, and still have not received a response. They are a small but well-staffed shop open 7 days a week. That's not how I would handle things if it were my business. To each their own, I suppose...

 

[MyDadSucks]

Im assuming youre on a santa cruz given the reserve wheels. Their derailleur hangers have always bent fairly easily for me, i would just swap it out, it takes about the same amount of time as all of that typing probably took.

 

[J.B. Weld]

My frustration with the shop is they replaced the derailleur and said everything was working as it should. This issue popped up on my first ride and is easy to replicate (my neighbor, avid mountain biker, rode it around the block and experienced the issue). Seems like the shop didn't bother to check their work or I don't have the right expectations for what the replacement of the derailleur should include. Additionally, I reached out to the shop on Saturday, 6 days after I was there, and still have not received a response. They are a small but well-staffed shop open 7 days a week. That's not how I would handle things if it were my business. To each their own, I suppose...

Ah got it, your op made it sound like you did the install yourself. Weird that you can't contact anyone from the shop, don't they accept phone calls?

If you want to tackle it yourself it shouldn't be that difficult other than the requirement for one specialty tool. I'd download the install procedure direct from sram's site and follow their instructions. Not positive but pretty sure one of their first recommend steps is to confirm correct derailleur hanger alignment. You can skip that step of course but if it's off it makes adjustments more difficult.

 

[Gunnar-man]

Check the links of your chain to make sure each one is straight. I had a mystery movement on my chain and shifting at one point and it turned out that one of the links had a pin that was intermittently bending and flexing.

 

[BrandNoobian]

Check the links of your chain to make sure each one is straight. I had a mystery movement on my chain and shifting at one point and it turned out that one of the links had a pin that was intermittently bending and flexing.

I will do this tonight. This is good feedback, thanks!

 

[baker]

Other thoughts...check chain length and b tension screw to ensure you are getting enough chain wrap...

 

[TwoTone]

Im assuming youre on a santa cruz given the reserve wheels. Their derailleur hangers have always bent fairly easily for me, i would just swap it out, it takes about the same amount of time as all of that typing probably took.

How does that fix a bent RD?
Horrible advice, even after replacing a RD hanger you should still use a tool to check it.
New != Straight

 

[MyDadSucks]

How does that fix a bent RD?
Horrible advice, even after replacing a RD hanger you should still use a tool to check it.
New != Straight

OP replaced the entire derailleur. You should read the entire post before you start shitting your pants.

 

[TwoTone]

OP replaced the entire derailleur. You should read the entire post before you start shitting your pants.

While I meant to say RD hanger, the second sentence makes it pretty clear.
So still a stupid suggestion since if you have the tool to check a new RD hanger, then you could check the old one before ordering a new one.

 

[MyDadSucks]

Hmm. Instead of resorting to 3rd grade insults…
OP, why not take your bike to a different shop if the original one is not responding? Derailleur hangers for santa cruz are commonly found (especially if its a Universal derailleur hanger from sram, found on newer SC frames), and a different shop should be able to check things out for you, since you don’t have the tool to check it yourself.

 

[TwoTone]

Hmm. Instead of resorting to 3rd grade insults…
OP, why not take your bike to a different shop if the original one is not responding? Derailleur hangers for santa cruz are commonly found (especially if its a Universal derailleur hanger from sram, found on newer SC frames), and a different shop should be able to check things out for you, since you don’t have the tool to check it yourself.

Might want to look back and see who started with the insults. How about answering the question?

 

[sailinginthesun6]

I was dreading getting back to some work I have to finish and thought I would see what is up. I would say that the problem you are seeing can be caused by hanger miss alignment, bent cage, top pilot wheel floating on the bearing (pilot wheel miss alignment), sticky or crimp in the shift cable, or as Gunner-man suggested the chain with a bent link, or drifting pin. Since you are running AXS you can rule out the cable but not the possibility of a index issue. From the picture on you post the cage was severely f’ed up. The rear derailleur alignment window is small and from my experience a miss aligned hanger or bent cage will usually show up in one section of your shift range, top, bottom, middle due to the travel of the cage from parallel to the cassette horizontally to parallel to the cassette vertically.
I would start by checking the things you can check first so you can rule them out or locate the issue. If you don’t have a hanger alignment tool you may want to get one. Changing a hanger will not guarantee an aligned derailleur, you always have to check it. Anything over about 1 deg or 3mm at the rim and you can start having problems.

 

[planetx88]

I assume you found this axs manual?
since its a new derailleur, it just sounds like a setup issue, which could be hanger alignment, as others suggest. Personally, I think its safe to assume a new hanger is straight.
Other things to consider.
measure chain at bottom out (take air out of the shock) , should wrap around easy cassette ring and chainring + 2 links (p. 31 in above doc.) Dont assume the chain is the right length.
Set b tension at 30% sag (also easily done with no air in shock) using white b tension setting tool (P. 39)
If you aren't already familiar with adjusting limit screws and the micro-adjustment function check out p.43-46 of that doc.


Honestly, Just follow the tech doc to the letter. I know that sounds sucky, but it is a pretty well detailed doc.

 

[Blatant]

Might want to look back and see who started with the insults. How about answering the question?

Seems like you’re being pretty aggro, man. The gentleman suggested changing the hangar. Pretty common and straightforward advice. If the OP’s incident was enough to thoroughly mangle a derailleur, it likely bent the hangar too.

Chill.

 

[flipnidaho]

I found that when I have shifting issues with AXS RD, it's almost always the B-Tension screw that is off (I've had the B-Tension screw back off over time so now, I always apply some blue Loctite on the threads).

 

[TwoTone]

Seems like you’re being pretty aggro, man. The gentleman suggested changing the hangar. Pretty common and straightforward advice. If the OP’s incident was enough to thoroughly mangle a derailleur, it likely bent the hangar too.

Chill.

How so, just said replacing a hanger was bad advice. Then he came at me, so I responded in kind.
You know a new hanger isn't always straight. So some that's new puts on a new hanger and still has problems and starts chasing their tail because they put a new hanger on and it can't be that.

 

[Blatant]

Ok.

 

[gregers05]

How does that fix a bent RD?
Horrible advice, even after replacing a RD hanger you should still use a tool to check it.
New != Straight

While I meant to say RD hanger, the second sentence makes it pretty clear.
So still a stupid suggestion since if you have the tool to check a new RD hanger, then you could check the old one before ordering a new one.

First off, you could have definitely responded in a better way, instead of calling someone's recommendations terrible advice and stupid. You mis-spoke from the get go referring to it as a bent RD. You cant expect any sort of nice response after starting out that way.

Secondly, it was not bad advice. 9.9 out of 10 times a new hanger is going to be straight. Replace it, keep the old one as a spare (after checking if it is straight). Or leave it on there and buy a spare anyways because everyone should have a extra hanger.