Suntour, rear derailleur doesn't pivot at mounting bolt.

Hobo

Retro Newbie
I’m currently rebuilding several of my old, road bikes. The problem I ran into was with a Suntour Cyclone, rear derailleur on a Centurion twelve speed that is probably from the early eighties. I should have been paying more attention but in my usual haste to get the job done I pulled the rear derailleur without noticing how it was mounted. My problem now is that I am reassembling it won’t pivot from the point at which it attaches to the frame. Looking at my other bikes, it should pivot in two places. It may be that I lost a spacer but I haven’t been unable to find it. On another of my bikes the mounting bolt has a shoulder that keeps the bolt from tightening down too far. On a second bike there is a nut on the backside of the threaded frame mount that is tightened to attain the correct spacing. The bolt on this derailleur doesn’t protrude through the threaded frame mount so it obviously didn’t have a nut to secure it. The bolt does have a shoulder but the shoulder is short by a fraction of an inch of being able to give the derailleur room to flex. When the bolt is tightened down it pinches the derailleur and won’t allow it to pivot. There isn’t a lot of room for any extra spacers. I did find one standard washer but it doesn’t do anything to help keep it free to rotate. Any ideas would be appreciated.
 
Here are some pictures that might help. Notice the mounting bolt. You can see that when it is inserted into the derailleur body that the shoulder doesn't protrude at all. Some derailleurs have a mounting bolt where the shoulder slightly protrudes. This allows the derailleur to flex on the bolt when the bolt is tightened down. On some other derailleurs the mounting bolt threads through the threaded frame mount and then the space for the derailleur to move on the bolt is adjusted by a nut on the back side of the frame. This one doesn't seem to have either. For one the threads on the mounting bolt don't protrude through the frame enough for there to be an adjusting nut. [http://i159.photobucket.com/albums...l]/url] Not too sure about this photo thing.
 
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