A drunken man walks into a biker bar

He sits down at the bar and orders a drink, looking around, he sees 3 men sitting at a corner table, he gets up, staggers to the table, leans over, looks at the biggest,meanest one in the face and says " i went by your grandma's house today, saw her in the hallway butt naked, man, she is a fine looking woman"
The biker looks at him and doesn't say a word, his buddies are confused, because he is one bad biker and would fight at the drop of a hat, the drunk leans over to the table again and says "i got it on with your grandma, she is good, the best i ever had"
The biker's buddies are starting to get really mad, but the biker still says nothing
The drunk leans over to the table one more time and says " i'll tell you something else, boy, your grandma liked it" at this point the biker stands up takes the drunk by the shoulders and says " grandpa, go home, your drunk"

Thanks for your time