Let’s see… This would count as an interest and/or talent, so it falls under “background, identity, interest, or talent”… and it seems like unicycling was meaningful to you, so, according to the Common App, “If this sounds like you, then please share your story.”
If I were an adcom, I’d find an essay like that to be very engaging. And I’m sure that compared with some of the stuff people write, this doesn’t come anywhere near the category of “weird.” Read the first two paragraphs of the following: http://www.nytimes.com/2014/06/15/opinion/sunday/frank-bruni-oversharing-in-admissions-essays.html?_r=0