Sweet trompe l'oeil. I don't usually go for skulls either, but this one looks like he'd better hang on for dear life at speed or get yanked down beneath the tyre.
The detail he has on it is unreal.... it's hard to see in the pic's he sent me but each star looks hand stitched and there is actually some thread coming off of some of them. Now I just have to think of something to go on the tank and rear fender for next years project.