That oil has a very odd color?
Anyway, the one cause I can think of as to how water might get in, is condensation: i.e. high air humidity where the bike was stored and colder temperatures for prolonged periods of time without running the bike - or something along those lines.
Last week, I finally fitted new valve stem seals on the V6 engine of my 1990 Ford Bronco that had been sitting for about a year. When I went to test drive it, after a couple of miles as the exhaust heated up, white smoke started bellowing out. Afted a few miles it stopped and I attributed that to condensation moisture build up inside the exhaust system.