Old 05-20-15, 01:50 PM
Senior Member
70sSanO's Avatar
Join Date: Feb 2015
Location: Mission Viejo
Posts: 1,314

Bikes: 1986 Cannondale SR400 (Flat bar commuter), 1988 Cannondale Criterium DA, 1992 Serotta T-Max, 1995 Trek 970

Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 236 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
First question... are the threads on the screw stripped/messed up?

Here are a few thoughts...

If the screw threads are bad, you may be able clean up the threads in the derailleur with a tap as suggested above. Or the "quick and dirty and hope it works" method is to go to Ace Hardware and pick up a 2 or 3 stainless M4 screws that are little longer and run them into the derailleur tension screw tab to see if cleans out the derailleur threads.

If the derailleur tension screw tab threads are bad and won't hold with a new screw, spend another quarter, or 2, and get 2 M4 stainless jam nuts as thin as possible. Depending on how far you need to screw in the tension screw, you can use either 1 or both of the nuts. What you are going to do is sandwich the derailleur tab between the head of the screw and the jam nut, or between 2 jam units. This is one reason why you want to get a longer M4 screw and use at least 1 jam nut width of adjustment.

If the new screws threads keep stripping out when you try to clean out the derailleur threads, I'd drill out the hole and use the jam nuts. This whole thing should only cost you a few bucks.

70sSanO is offline