So apparently, my friend overfilled the oil on his old 85 ninja (as in 6 L, when it should only be 3.2) - the reason was because he was going by the little window, which didn't show much change (go figure - must've been dirty or clogged).
when he started the bike, he said it engine oil started coming out of his airbox, leaking all the way down the bike.
by the way, this was last year (probably october).
The only way i can think that the oil got there, was it overfilled the pistons, probably blew some gaskets, went up through the carbs and into the airbox.
He tried cleaning it as best he could with towels. But even now, i can see (and feel) much residue from the oil.
He asked me to help him take a look at it. When i tried to start it, the starter barely spun (probably oil leaked on it), to the point that now, it doesn't do anything.
i also tried to hot wire it (the battery directly to the starter), and it still spun slowly, then died.
My question: how do i go about cleaning the oil off? Use gasoline as a solvent? And should i take apart the starter, to go about cleaning that first?
Thanks for all the help! cheers