Drunken Chicken

Hi all!

I recently uninstalled my old drivetrain off my Hardrock. As I removed the Acera R/D I think I damaged the threads on the hanger. I started screwing in my X7 derailleur and alas, it won't go in straght, only at an angle and not even fully. I checked the hanger threads and sure enough they were damaged, not only that, when I screwed my X7 in the threads took on another shape which meant that whenever I screwed the derailleur bolt in it would go into the hanger at an angle, not straight. I was nearly set on buying a new hanger but being the cheap person I am I tried a last resort: I took my Acera derailleur and screwed the first thread in. I then forced it into a straight position and kept on screwing it in, basically making the threads in the hanger "more or less" right again. Here's the thing: I can screw the X7 in all the way except for a last thread on the bolt. It goes in only at a very small angle now. The thing is, my hanger is very slightly bent inwards and with the der. bolt showing one thread and the der. being at an angle, the derailleur is at where it *should* be, in terms of position in relation to the frame.
Is it safe to use it like this? Should I just buy a new hanger?
In the below diagram, the green lines represent the position of the derailleur bolt where it SHOULD be, in relation to the hanger. The hanger, as you can see, does not go horizontally across the diagram which is supposed to mean it's slightly bent inwards (towards the wheel). The red arrow is pointing to that last thread sticking out of the hanger. The orange part of the diagram is the frame. The thread at which the red arrow is pointing at should be at the same height as the frame and should go 100% horizontally on the diagram showing it's in line with the frame.

Excuse my crappy picture and explanation, if you want I can draw a better pic and scan it.

Cheers
-DC

HillRider

If the derailleur isn't installed straight, shifting will suffer a lot. Get a new hanger and be grateful you can.

Retro Grouch 

7-speed. Does it even have a replaceable hanger?

If it has a replaceable hanger I'd get a new one, in fact, I'd get two just so that I had on on hand.

If it doesn't have a replaceable hanger you need to buy a part that's called a "dropout saver". It's an insert with shallow wrench flats that you can install after drilling out your hanger sligltly oversized. If your hanger is bent, it needs to be realigned. Bike shops have a tool for doing that and the job usually only takes about 5 or 10 minutes.

Drunken Chicken

9 speed drivetrain, it's a Hardrock sport so hangers are replaceable. I'm leaning towards getting a new one.

Svr

You could always try cleaning out the threads with an M10x1.00 tap.

Replacing the hanger is the best option, but you could give up several weeks of riding waiting for one if it has to be ordered.

a77impala

You may try screwing it in from the back side, that should straighten the threads
enough to let you restart it straight again. You should be able to get the right size bolt at your local hardware store.