I am not a mechanic and even if I was I have never seen this issue before. The mechanic at the Co-op hadn't seen this either and thought the bike is done (or would make a fixie frame only).
I am helping a friend who bought a $20 Norco 10 speed with a Shimano Light Duty drive train. He had shifting issues and I couldn't align it properly. Either the rear would be aligned when using the large chain ring or it could be aligned to the small ring but never both. To my eye the RD seemed to have "bit" of play (it could sway slightly inwards and outwards).
I brought it to the co-op and was advised to try stripping out two chain links (chain was very loose) but that didn't save the day. I tried a second RD and found that it's hanging bolt was loose in the hanger. I stripped down both the old and the second RDs and discovered that the original (old) RD was missing an internal seal. With the seal gone the hanging bolt would reach just that much farther through the RD and thread into the hanger (only a tiny bit). Because it was so loose it had stripped the threads of the hanger.
Since he will need a new RD I'd like to do this reasonably inexpensively. I see online that I can get a 7mm dropout saver for about $20 but also see dropout saver kits for $70.
Do I need a full kit or can I just order a single saver?
Also do I simply use an 11/32 drill bit to widen the existing hole? Should I find a drill press instead of a hand drill? It seems too easy,which is also why I am asking before I go get a dropout saver.
Lastly could I just get a claw hanger mount and attach that to the frame in the hanger hole and then attach an RD to the claw or will that not work because claw hangers are usually mounted to piece that fits in the drop out?
