I have carried a full, full sized keg on my Xtracycle (same rear end as the BD), and it is definitely doable. I strapped it onto the Wideloader (horizontal platform) on the right side, using nylon web cargo straps with the keg lying on its side, and had to ride leaning over at about a 10 degree angle, but I actually got used to it after the first 1/2 mile or so. The whole ride was just under nine miles, and while I didn't go very fast, I was leaving the tallbikes behind (drivetrain problems slowed them down). The best part was having a centerstand that would hold the bike with a keg on one side; made everything much easier. I will admit that an 8 Freight, a Longjohn or a Van Andel style Bakfiets would probably work better, due to the ability to center the load. I didn't have one of those, though, so the ride went on.