You have to pry them off. They are a friction fit, the pins on the back of the emblem push into clips that are friction fit into holes in the bracket on the tank. I would recommend a thin plastic ruler or plastic putty knife to start with. The clips may disintegrate upon removal, but they can still be had new from Honda. Just use care and try one end of the emblem, and then the other end alternatively until it starts to budge. It can be done without damage if you take your time and don't get too ham-fisted with it. Personally, I would have preferred screws here...
