I remember that bike
Flyin:
Did you maybe drill a new oil hole in the improved location or are you just thinking of resetting the adjuster (push a screwdriver in the back to release the plunger).
Murray was working on a kit to modify the automatic tensioner adjuster's plunger and JC even made an instruction page for it on Motofaction but for some reason it never went into production.
Some fellows in Germany are rebuilding them on a small production basis so replacements are available if/when they self destruct.
I think changing to the manual adjuster is probably the best solution, though. You just install the manual adjuster (a thread adapter is needed but the hole is in the same place), replace the tensioner (blade) with the manual type and use a rear engine cover from a n engine that came with the manual adjuster.
We in North America think of this example of design change to protect people that don't properly maintain their equipment as only applying to he CX/GL650 but most of the rest of the world got them the 500s in '81 & '82.