When I got my B6 it had been sitting unused for over a year. I pulled the tank and drained it and the carbs. Since the tank was off I put in new spark plugs. Air filter was fine so I just put in a new battery. I drained the oil and put in fresh so I knew it was okay. I then put in fresh gas and it started up and ran good (as good as a non-jetted B6 can run). If you had fuel in the crankcase I would put in some cheap oil, run it a few minutes, drain, then put in the good stuff. If your carbs have gummed there are some good posts about adding in some Chevron gas additive.