i spent some time tinkering with the emblem on my CB500. figured i'd remove it since the tank will be in the shop for a paint job. i noticed that the Honda logos were held to the tank in a way similar to the logos on the side covers. heres a few steps i took to remove the Honda logo from the tank with no probelms in less than 20 minutes.
1. a small straight blade knife works well to loosen the emblem. use a rocking motion, start on one end and switch from prying the top of the emblem to prying the buttom of the emblem. a butter knife works well at this point for added leverage for prying. once you can see the emblem post and where it is mounted, you can move to the opposite end of the emblem. a flashlight will be helpfull
2. find small nail that is long enough to reach the clamp holding the emblem post to the tank. position the point of the nail between the wing of the clamp and the post. tap the nail a few times and it should bend it from the post. there are two wings to each clamp.
3. if both wings of the small clamp are pried away from the post then you can pull on the Honda emblem and it should pop right off.
4. bend the wings back in on the small clamps and pop them out.
and that's what worked for me. I'll try and post a simple picture of the process.