r80 is wrong, black is best. Seriously, a good thing to do is measure how much oil you remove at oil change time. Not all of it gets out of the motor. For me its been a little less than 2 qts both times. Then put that much new oil into the motor, being sure to soak the filter (I put it in the funnel and pour the oil over it on its way into the motor).
+1 on the last two posts, we need to define over filled. The top of the site glass is over filled. Lots of people who fill to the top get blow out into the air cleaner. I fill to the mid line mark cold but haven't had any problems. Try dropping back to there cold, then a little lower if you need to.Scott