Rent a bike and let someone else deal with getting the sand out of the bearings, bushings and any other moving parts. Sand is just about the worst thing you can get in a bearing and it will find a way in, no matter how careful you are. Just think of all the places you find it when you are coming home...the car, your shoes, your hair. Unless you like to tear your bike all the way down for fun, I'd save yourself the hassle.