How old are you? This is a serious question, because God protects the young and innocent but punishes the stupid and those old enough to know better. If you try stunts as crazy as this when you are under twenty-five and have only two years' experience with bikes then you'll probably get away with it, but if you have more years, in either sense, then the laws of physics will apply as usual and you'll pull the luggage rack off the bike, shred the tires, break the spokes, ruin the gearbox output shaft bearing or simply end up in a big heap with both bike and boat on top of you. But let us know how you get on...