If your vehicle is packed tight, then you shouldn't worry about it shifting. If you put it on the motorcycle chocks and surround it with big objects first to take up all the space then it should not shift. You won't need to screw it down to the moving truck unless you want to pay them thousands of dollars for the repairs. Just because they don't notice it right away doesn't mean they still can't charge you for it. If all else fails, leave the bike at a friends, come back with your wife and then ride it down
