Are you seriously using "gay" as a derogatory term? What are you, 14?? Grow the hell up.
Now, if the question was: Is it weird to sing along with the radio? I'd say, hell no. Whether they admit it or not, everyone does it. Beware though, on a bike, anyone/everyone can hear you much easier than you can hear yourself.
This post is more annoying than someone singing on their motorcycle. It is a derogatory term just like f.a.g., queer and homo.
If you want to sing along while riding go for it. I have an mp3 with highway music and roll on the volume with throttle as soon as I hit the highway.Sometimes I'll sing along,so what. I enjoy it don't give a rats *** what anyone else thinks. Keep the volume down around town and crank it up on the backroads and highways. It's not about the weekend catwalk empty your wallet follow me cattle runs.