My 91 fatboy needed a new clutch cable, so I loosened the exhaust and removed the cover, and a bunch of grey thick oil came out. I also see that somebody has put a bolt or something into what looks like the breather tube for the transmission. Is there something that I should know before I put it back together and put fresh 20/50 into it? I haven't seen anything about grey oil when I googled, so I thought that I would give y'all a try. Thank you.