sualfred

Hey there,

I'm driving a Cube Attention (2023) L/29" with a 2x11 drive and I'm having troubles with my derailleur.The chain swings as hell and always hits the small metal piece of the cage (Leitblech in German, dunno if "baffle" is the correct word?).

What I've already tried:
Switched from Deore M4120 to M5120
Switched chains (a new one works for some kilometres)
Switched derailleur hanger
Checked the derailleur hanger for correct allignment
Cleaned and oiled the pulleys
Readjusted the derailleur for 128392737x times (B/H/L screws + tension)
Tested 112 instead of 114 chain links (11x42T cassette, 450mm distance, 36T on the big chainring. 114 should be the correct size based on the calculators)

Any idea anyone? It's driving me nuts!

(@mods I'm sorry to bypass your 10 posts rejection for external links, but I don't wanna spam useless things to other threads and the files are toooooo for an attachment here)

For the videos, please manually remove the spacer of the urls

Short clip in normal speed:
amazon . de /photos/share/6BbIWgJHTabf5B0OJ5vWBj1PSkEfHWmlzxmKvQXiZaG

Slow motion (very noticable at 40s<
amazon . de/photos/share/77GXhbiTi4KLpmQWEy7RONkK7QuAIcYnrhgIWZYzjcz

Thanks in advance guys!

mpetry912 

I think I know what is wrong.

the pulleys are switched top to bottom. The "tell" is that the top pulley has the "shoulder" on it for better shifting, and the bottom pulley is a little bit larger.

Take the whole cage apart and put the bottom pulley on the top, and put the top pulley on the bottom. will shift better too

Be sure to check that the pulleys are going the right direction - the shimano 11 speed pulleys have "arrows" ( -> ) pointing the direction of correct rotation

I think that's it.

do that and report back !

/markp

sualfred

thanks, but they are correct. Bottom one is the tension pulley and the one with the larger teeths is the guide pulley. Only the tension pulley has an arrow for the direction.

Iride01 

I consider myself a pretty avid DIYer. However for 2023 bike, it's new enough that I'd take it back to the shop I bought it from and expect that they'd fix the issue for free. Unless they could show that it is something resulting from my mistakes. If you bought it online, then call them. They might ask you to take it to a authorized dealer or repair facility. If for nothing else than a free estimate of what it will take to make it work again.

Long ago, taking bikes to the shop gave me a chance to watch the mechanic as they worked on bikes and I learned a lot just from watching.

Crankycrank

I can't see from the vid so just throwing this out there. Are you sure the upper pulley isn't too close and contacting the cassette teeth and is the chain routed through the top of the cage properly, i.e. not riding over one of the cage tabs?

SurferRosa

Link assist:

https://www.amazon.de/photos/share/7...SBGhMQv_O2CLyA


Sure looks like the problem is the intersection of the jockey (upper) teeth and chain.

maddog34

look at the teeth on your Smallest sprocket on the Cassette... now, compare them to the teeth on the top jockey wheel...

the tooth profile of the jockey wheel is your problem.
file 1mm off of each jockey tooth, then radius the tops

Example: https://www.ebay.com/itm/12559495309...72bf7982ca9ac1

sualfred

Thanks, I already tried that. Nothing changed. Exactly the same behaviour. I'm running out of ideas.

frankenmike 

Very strange. I’d be tempted to just remove the offending tab. Is it possible that something is interfering with derailer tension? Also, with the chain removed, do the pulleys spin freely?

Schweinhund

The teeth on the upper jockey wheel are too wide for the chain.
WAG: wrong chain.

sualfred

Yep, they spin freely, but I also find the complete chain movement a little bit loud. And it vibrates as soon as it swings. But no clue why, every gear shifts perfectly.

The chain is correct HG701-11. I would paste a link or screenshot of the Shimano compatiblity list, but the board won't let me do it yet It also fits perfectly in the pulley.

Schweinhund

Please post a shot of the chain alignment from the direct from zero (directly behind) perspective. we can't see the meshing of the chain to the pulley from a non-zero angle perspective.

frankenmike 

One last thing-try sizing the chain manually using the big-big +1 method.

Schweinhund

Something in either your model or setup is not correct. That something is in an isolated area that frankly is dead assed simple to diagnose.
Derailleur hanger, derailleur, chain, chain alignment (shifter/derailleur adjustment)
From the sound/visual the first thing I thought was the jockey wheel riding on the side plate of the chain and then shifting over and dropping into the link.
initial thought is that you would catch that. now I'm not so sure.

grumpus

That's weird - looks like the tension pulley is too small, but that's not likely from the factory. I'd try fitting a larger one anyway, they're really cheap on AliExpress

sualfred

I did that yesterday for a German board, are these pics what u r asking for?
(sorry, had to bypass the external link protection again)
amazon . de/photos/share/TjjJ8gsyQf9dUHHpbdwmAeU7nifmd3vhkCveJ6ddST0

There is also a slowmo from the back. It's possible that some pictures or the video have a different b-screw setting and a shorten guide pulley. But nothing made a difference.

I did that when I was installing the M5120 at the same time (112 links). Tried a few rounds around the block and it was toooo short. Hard to shift (especially on the biggest one). The chain tension was from hell and on big/big there was nearly no play left. The cage was sitting around 3-4 o'clock in this combination.
The shipped chain had 114 links so I reverted back and the tension is absolutely okay. If I would add 2 links more, it won't be tight enough for small/small or small/big.

Deraileur hanger adjusted, replaced, and adjusted again.
The first installed chain was a KMC x11 which is even worse. Than I replaced it with a 701 and it was fine for 100km< and out of nowhere it started again.
Installed a third chain, again a 701, fine for a few minutes, problem was back.

Schweinhund

Post the picture/video I asked for and maybe we can figure it out. I'm going to stop with the conjecture. Need more info.

sualfred

I'm having problems to understand which perspective u want exactly. EN is not my native language, sorry

Schweinhund

I and many of the gentlepersons here have been working on electro-mechanical devices for all of our days.
We fix stuff. Given all of the data we need we can figure out most anything. Something is missing here.
The chain issue just makes me think your adjustment is incorrect. You put a new chain on force side plate wear and once the side to side wear is a issue it makes noise because the chain isn't holding alignment anymore. The chain isn't supposed to hold alignment, the cable/ screw stops do that.

Schweinhund

I think this is what you have going on, a slight mis-alignment. it's wearing the sides of your chains out.
zero angle.

just barely misaligned. the high limit screw is the problem

sualfred

I don't have really room for the H-screw. If I slightly increase it, it will rub on the gear. Loosen it doesn't change anything.

amazon . de/photos/share/uDNNs1Rp4qe8hAxCzvBYmDBfRO3oPGnjbv16Hvm6wF1
and from above:
amazon . de/photos/share/PXC4A1mWkepwyLyuMUFlajgz9mImseeO5Qk84hmGvP2

Eric F 

It looks to me like the lower pulley is too small. As mpetry912 commented earlier, I think the pulleys are in the wrong spots. The larger pulley should be on the bottom.

EDIT: This ^^^ is incorrect. The jockey wheels are in the correct placement for the M5120 derailleur.

mpetry912 

thanks EricF sualfred suggest you swap the pulleys.

otherwise you're just grinding it up

you asked for help, you have a recommendation, make the change and report the results

help us help you

/markp

Crankycrank

I thought so too but lets put this to rest. Large pully on top, small on the bottom for this derailleur. SHIMANO DEORE Rear Derailleur SHIMANO SHADOW RD+ 2/11, 1x10, 2x10-speed | SHIMANO BIKE-US

Eric F 

Yes. I just found a pic of the back side of the M5120 that clarifies the proper position. My previous assessment is incorrect.

Looking at the video, I don't understand why the chain is bouncing so much. Something isn't right.