Maybe this will help? http://www.mainzerruderverein.de/index.php?me...

Danke, hatte auch schon ein "online Ruder-Wörterbuch" und damit auch das Wort pin gefunden. Leider kann ich mit "work through the pin" nichts anfangen :-(

You've got the idea: you use the pin to adjust the height and the work.
"Work" seems to mean the same as "drive" - what you are doing when pulling the oar through the water; the opposite is "recovery", when you lift the oar out and move it back to the front. Perhaps you can use the pin to adjust the arc of work. See here: http://www.lrc.com.au/doc/EasyOar_Apr08.pdf
("In a faster boat you want more work in front of the pin, and in a slower boat more work behind the pin.")

Aaaah! It's by means of the pin... So: Höhe und Dolle verstellbar über Stift.
?

None of my rower friends are online, unfortunately, so I can only really provide useful help with the syntax :-(
From that pdf, though, it looks as if the Dolle/swivel is the rotating thing at the top of the pin. If that adjusts the arc of work, then maybe.

Anlage ist der Winkel, den das Ruderblatt zum Wasser hat, wenn das Skull (Ruder) flach auf dem Wasser liegt. Dieser Winkel und die Höhe der Dolle (über dem Rollsitz) ist normalerweise am Dollenstift einstellbar.