Is it normal for a female to be be turned-on by pretending to be male?

I'm not really into cross-dressing or trying to look butch or anything like that in public, nor do I feel like a "man trapped in a woman's body". But sometimes when I masturbate, I like to imagine that I have a male body, with a penis and the ability to ejaculate and all that. Sometimes I imagine myself having sex with either a woman or another man, or just masturbating as a man (I'm bi, so it's the same deal with the fantasies where I have a female body, too). There's just something about the idea of having my sexual parts on the outside of my body, "on display" so to speak, so I can neither fake nor hide being aroused or having an orgasm, and the knowledge that my sexual response and eventual climax serves an important biological function in terms of reproduction (at least potentially), that I find really hot. So, is this normal?