oil leak

i seem to have an oil leak possibly from high left side but i clean it run it and no oil leak???
this has happened twice both times i take off the fairing can't see where its coming from clean it and no oil leak go for a longish ride still no oil leak.
the 2 times have been popping down to the shops [short run] any ideas thanks [1989 gpx600]
this has happened twice both times i take off the fairing can't see where its coming from clean it and no oil leak go for a longish ride still no oil leak.
the 2 times have been popping down to the shops [short run] any ideas thanks [1989 gpx600]
