Is my derailleur bent?

Dumb question. Is this bent? Shifting is all wack after crashing and I’ve never crashed so unsure if this is bent. Would rather ask here before LBS given the wait times right now.

Top pic sure seems to show an angle that should not be there. I think the frame derailleur hanger is bent, and needs to be straightened, preferably with a proper alignment gauge for best results. Or you can replace the hanger if you have access to one.

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Neither of those pics are particularly square so it’s impossible to say. But it’s very likely that your derailleur hanger is bent. Which is supposed to happen in a crash so that it takes the force instead of your derailleur ($10 vs $200). Though that first pic makes it look like the hanger is bent a fair amount. A bike shop should be able to straighten it out for you or sell you a new one.

The r8000 cage has that little bend in it. However especially looking at the first pic your hanger is 100% bent

Here’s my cage

Here’s your issue
image
Vs a straight hanger

I had the same problem on my MTB

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Looks bent, agree with others

Even if you have a shop straighten it for you, order a replacement. You should always have a spare hanger for your bike, particularly if you’re riding one that’s been bent and straightened

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It sure looks bent from the photos. How is the shifting? If your RD shifts are crisp, on target, and there are no skips with the chain, then maybe it’s not bent.

But, if you have some shifting gremlins messing with you and no matter how many times or which direction you turn the barrel adjuster, your chain manages to skip somewhere along the cassette, odds are it’s bent.

Thanks all. Shifting is uh, no bueno. Some shifts are fine but when shifting into the low gears in the back, the hanger hits the wheel spokes. Never had to change/replace one before so obviously very new to this aspect.

  • Already stated in the OP:

Yea the further inboard you go the more “off” the derailleur becomes because those lines I drew cross and then get further apart. Changing hangers on Di2 is cake, mine was held in with a few screws and then the derailleur bolts to it. Should be a 3 minute job. I went with Wheels MFG for my replacement it cost $17

That would be - the derailleur cage is hitting the spokes. The hanger is the bit of frame (replaceable in most cases) on which the derailleur is mounted.

Park DAG-1 is the DIY solution - it will probably cost the same as the visit to the shop. The next time you bend a hanger, you’ll be ahead financially :smile:

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One should really do a hanger alignment after replacing a hanger, however. You have no other way of telling if the frame and hanger faces mate exactly, if there was any deformation of the hanger mounting points on the frame, etc.

My skim reading fails me again.
Sorry 'bout that.

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Notice how he’s doing an alignment because he replaced the hanger?

That was my point 7-8 posts ago.

I would play this game with myself from time to time & depending on my mood could convince myself the derailleur was either bent or straight. :smiley: So, for sure, I’m not going to be able to tell from your pictures.

I eventually bought a gauge for ~$40. It’s nothing special but it does the trick. I’ll link it below. Also, I think wolftooth makes a gauge that is very elegant…basically two tubes that are long enough to eyeball & know if they are parallel. If they are, bob’s your uncle. If they aren’t you’ve got plenty of leverage to adjust. But that gauge is a little pricey.

If you suspect a bent hanger, here is an easy test. Push your derailleur all the way into the big cog by hand, pushing as hard as you reasonably can. If your chain drops into the spokes, it is likely bent (unless the limit screws were already off and you’ve been magically getting lucky).

Replace the hanger and/or straighten it. So far I have only bent a cage once, and that was when a piece of rebar got sucked up into the rear wheel. I have tossed my MTB down some pretty rough crap and yet to ruin a derailleur, but I have been through many hangers (and many straightenings).