I was adjusting cable tension on the RD tonight. RD is 9 speed Dura Ace. When I went to put the bolt back in it acted as though it was stripped. I noticed a spring like object lying on the floor below the RD. The spring seems to wrap around the bolt and looks like a close fit, if I could get it to go back in the bolt hole.
Is the 'spring' I've found a replaceable part, or did I in fact strip somehting out from inside the RD body? The bolt itself looks ok.
I've been doing some research and I think the spring I found is actually something called a helicoil. It's used when you strip out a thread hole. I'm the second owner of the bike. I'm going to see about getting a new helicoil and the insertion tool and see if I can get it back how it was. The components are about 8 years old or so I think the previous owner might have stripped it out.
In case anyone else every gets in this situation you need a 5mm helicoil with a .80 pitch for the pinch bolt on a DA7700 RD. I got the kit for $25 at an automotive store and I'm going to give it a shot tonight.
The kit comes with a tap, an installation tool and about 10 helicoils. The instructions say to drill the hole out to a certain size, then use the tap to claen the threads and then to install the coil. A guy at the shop told me that since the RD had this all done once before, I should skip the drilling and just 'chase' the threads with the tap to make sure they are clean and then install the helicoil.