I have an 86 Venture and have a similar/same problem. I have gas running down the left rear carburetor joint (carburetor boot) and I cannot tell where it is coming from. I noticed it about a year ago but it was rather insignificant and I would just keep the area clean. However, it now is to the point that I am concerned about the bike starting on fire. I have several parts removed from the bike as I just did a valve clearance check. I am going to try some of the suggestions on this post and hope for the best. I would like at least like to get through the summer riding season and possibly rebuild the carburetors next winter.