To answer the agonizing question for nekkid bicyclists,
you ride standing on the pedals.
Don’t ask me how I know.
How do you know? 
A philosopher on a bicycle… that image has a certain poetry to it. A nekkid cyclist…a certain humor. But a nekkid philosopher on a bicycle…truely a conjunction of the sublime and the rediculous
There’s good naked and bad naked. I’m afraid naked bike riding is the latter.
Way back when I was in shape, I and a buddy were racing up a hill; I was standing up on the pedals. Out of the corner of my eye, he drops back and just disappears. I turn around and he had his hand over his groin. I stop, coast down and ask what happened. He ran into a bee with his crotch-or the bee ran into him- not a good thing.