xs400 rebuild

I just bought a 81 xs400 special about a month ago. I have no clue if it's a sohc or dohc as i have not dug into it yet. But the point of this post is that my oil 1.) Reaks of gas 2.) Had almost 5 quarts of oil in it before changing oil. Somewhere on the site I read that my bike requires 2.4q...