It weighs 25# + bike 30# = 55#.
check www.shuttlebike.com
and
http://www.catsailor.com/bb_files/67017-SetupDay2.jpg

That looks like what I have been thinking about, except I never thought to make it inflatable. Any idea where I can find one in the US and what it costs? Looks like fun and not too much trouble to set it up.