Leaking oil along tachometer cable

[stoop104]

Help!
I own a honda cb 750 '81 and he is leaking quite some oil along the tachometer cable.
Someone has an idea what could be the cause?

 

[HerrDeacon]

Probably just the oil seal has decided it had enough. Part should be still available and cheap. Just disconnect the cable from the head to see if there is any oil coming out there.