soak with penetrating oil around shaft
I just love your sound effects!
We've had at least one or two reports of the adjuster locking up. I'll have to see if I can find them...
Ok, try some Liquid Wrench Dry Lubricant. You don't want to use something like WD40. You may also have to use a strap wrench for some extra oomph...
http://www.amazon.com/Liquid-Wrench-L512-Lubricant-CERFLON/dp/B000CPJLE4
Don't know if you can get it in Italian....and if you can't, I'm sure you can fabricate it.
Here's the only thread I found. I think that there were some more but they were lost in the old forum..
http://www.zggtr.org/index.php?topic=11886.msg145975#msg145975