Removal of Seized Stroke Adjusting Screw of Rear Derailleur

[mtbvfr]

Apologies for the Amazon ad. but I do know these are excellent in similar situations and have got us out of bother a few times...

https://amzn.eu/d/giEeRUG

I haven't got back to it yet but I was thinking of needle nose pliers myself after giving the derailleur a 7 day soak in WD-40 and trying the correct size JIS screwdriver without luck.

I don't think I had seen the design of what you mentioned however. Thanks!!! for the heads-up.

 

[DaiP]

The only other thing I can think of, other than everything that’s been suggested so far, is a suitable size drill with a left hand flute and run the drill in reverse. Problem with that is it’s tricky due to the small diameter of the screw and if it doesn’t work you’re probably only then left with completely drilling out the screw and having to put in a helicoil type thread repair.
I like the look of those pliers on Amazon though. They’re something I’ve never see before.