Sachs-Huret Eco S rear mech problem

gtd.

My rear mech keeps either getting slack or too tight, Its a Sachs Eco S like this

The screw that goes through the cage and upper jockey wheel is either always too slack causing sloppy shifts or too tight so the cage doesn't take up chain tension.

Any ideas to sort this? The screw threads into unto the parallelogram then has a lock nut but as it swings back and forth it slackens up eventually giving a lot of slop or sometimes after trying to adjust it it gets tighter and wont take up slack.

el_presidente

I'd suggest a new budget mech, I suspect that one is dead.

rolf_f

Post on Retrobike forums. This is more their sort of thing.....