I've replaced chain and dropout hanger. The rear derailleur is Shimano Claris. When I'm turning pedals chain (Shimano hg-71) is touching small plate (marked with red arrow) between high (closer to high) and low pulleys with loud metal sound.

The derailleur works in general and I'm able to switch between all 8 gears.

How I can solve this issue or is it broken?

There are also video, where it is obvious in action https://drive.google.com/file/d/1aEuVgdymEKdN0EWf3sq25GhJhyD7SK0k/view?usp=sharing

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UPD: Solved - I've bought new derailleur(claris ~20 eur) and I was able to configure it very easily. The problem in old one is really in broken inner plate geometry. This probably happend during my accident. Plate is bent in X axis towards towards the chain, which makes it really hard to bent back.

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    It's unclear what you're describing (I can't identify the thing pointed out with the arrow), but it's not unusual for someone to route the chain on the wrong side of a pin in the middle of the derailer arm that is supposed to keep the sides apart and keep the chain from becoming tangled if it goes loose. – Daniel R Hicks Jul 3 at 20:27
  • Actually, that "thing" may be the end of the spring that tensions the arm, and it may have gotten dislodged from it's proper position. – Daniel R Hicks Jul 3 at 20:30
  • That is possible, as I was in an accident. My chain get jammed and dropout hanger broke. The deraileur was hanging on the metal thread. The chain was broken . After that i was trying to replace chain and dropout – dzift Jul 3 at 20:39
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    It is a bit hard to see the details in the photo, perhaps you could edit in others from different angles. – Swifty Jul 3 at 21:01
  • Is the upper wheel turning properly? It seems like the only way for the chain to hit the tab would be if it is riding up over the teeth of the pulley wheel rather than the wheel turning – Andrew Jul 3 at 22:58

It's weird because that metal tab should be there, and the chain should be that side of it, without contact. It's there to catch the chain in case of derailment, and would normally be closer to the outer cage plate.

The two main plates of the derailleur cage don't look parallel to me, which would suggest they are bent out of alignment, perhaps from the crash damage. If that is the case and it is pulling the tab up closer to the chain, this could be why it is contacting the chain.

In theory you could reshape the derailleur side plates somehow, but I practise if they are misshapen like this then it's a case of replacing it. Another unfortunate expense of the accident.

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  • I think this is very possible. both plates are very bendable. hovewer, I was not able to bend them right way :) – dzift Jul 3 at 21:50

Based on the picture and the description my best guess is that part of the inner or outer cage plate (part number 3507 or 926) isn't quite straight. A little strategic bending might be in order to prevent the chain from rubbing.

I know this isn't your derailleur but here's an exploded diagram with part names for reference. I couldn't find a Claris diagram.
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Either a small part of the cage is bent into the path of the chain or the whole cage is out of alignment. The pulleys and gears should be aligned throughout the shifting range.

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  • Do some careful analysis on exactly what is bent.
  • Determine where force needs to be applied to gain the desired result.
  • Then apply only enough force - to get things straight.
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    I've bought new one, it will came tomorrow and I will check how it work on another one, On this one I will sharpen my bending skills :) – dzift Jul 3 at 21:51
  • @dzift That is a great idea! You get better at what you do. – David D Jul 3 at 22:03

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