Originally Posted by
stephr1
Re: Hanger...the RD mounts directly to the frame. There is no extra metal piece/hanger that goes between the RD and the bike. However, I have noticed that there may be too much play in this area (given the age of the bike, I had been thinking about a new RD and this may be the moment) and this could be the same as a misaligned hanger with no way to readjust.
The good news is that's a steel frame bike. They tolerate the following better than aluminum bikes do.
1. Shift into a gear combination that makes your derailleur arm point straight down.
2. Prop your bike up vertical and look at it from the back.
3. If your derailleur arm seems to point toward the wheel - that's it. It should point straight down.
On a 7 or 8-speed I can eyeball it back into alignment so that it's "good enough." On a 9-speed, I need to use the alignment gauge. If you're up for trying it without the gauge:
1. LEAVE THE DERAILLEUR IN PLACE! If you remove it, you can ovalize the derailleur mounting hole and I don't know how to fix that.
2. I either clamp a big Crescent wrench around the derailleur and mount or, sometimes, I can do it with just my hands.
3. Just armstrong it back so that the derailleur arm points straight down.
Good luck.