[PoorCyclist]

heavy wind caused my bike to fell.. RD body contacted the pavement and got a little nick, the pulley did not appear to have touched anything

How can I tell if there are any damages, I don't think the hanger is bent since it looks pretty thick.. it seems to shift and look OK, didn't shift into the spokes or anything, could be shifting to the smaller cog a little slower but this could be all in my head.
so with a minor impact like this, do I keep riding and not worry too much.

Assuming the pulley and hangers are stragiht, could the RD body excluding the pulley part be bent or tweaked by such impact?

 

[mainlane]

Go ride and seeeeee what happens...

 

[411898]

They are made to take abuse. Hardly a rear der out there that isn't at least a little beat up from making contact.

 

[Squash]

If it's shifting slower to the small cog (s), then the hanger is likely bent a bit. If it is or you think it is, just take it into a shop and have them check it and align it if necessary. It's a 10 minute job. Derailleur hangers, while fairly thick and burly looking are not as stout as the derailleur itself. That would defeat the purpose of the hanger, which is to save the frame and the derailleur should they take a hard hit. Hits that don't hurt the derailleur can still bend or break the hanger, even tip overs can bend the hanger. So if your worried about it, or the shifting is off, have it checked.

Good Dirt

 

[411898]

That reminds me, my wife had a small crash on her new bike last week. The brunt of the fall went on the cranks and the rear der. The der. hanger snapped and she bent the cranks a little. New, better cranks already in the mail! I replaced the der. hanger, no alignment issues even though the der. has a sizable grinding mark on it now, lol!

 

[FBinNY]

One of the nicest things about index shifting is that it's an instant indicator of any change in the hanger position.

If the hanger got pushed in, all the shifting would be offset toward the inside, so the trim will be off and it'll be slower to shift back toward higher gears. If it's bent far enough the RD position could be moved in by an entire sprocket.

If the shifting is as before, all is good, and nothing needs to be done.

One thing you should do, not only after a crash, but every once in a while as a safety check, is to check the inner limit screw setting. Have someone hold the rear wheel off the ground and shift to low while turning the pedals by pulling the inner wire away from the frame as if drawing a bow. If the chain goes beyond the innermost sprocket, or even if it hangs on it contemplating going farther the inner limit needs to be brought in.

 

[straw]

Did the same thing. Propped my bike up while closing the house door and a breeze blew the bike over onto the RD. The shifting was off so I just tweaked it back and everything was golden.
Cheers,
Straw