I think a lot of it has to do with how good of a bike rider you were as a kid and how much of a risk taker you are. I got my first bike when I was about 4 and rode a bike all the time up to when I went off to college. As a kid I could ride a wheelie for, no kidding, about an 1/8 of a mile and could ride no handed probably by age 7. I used to ride a bike to school in 7th grade and it was about 5 miles one way. I didn't have a backpack, didn't carry them back then, so I had to carry my books with me on the bike. I could ride almost all the way to school with no hands, including cornering. When I started riding again, after a layoff of over 20 years, I was a bit shaky for the first day or two. But was able to ride no handed again within the week. I remember riding in one of my first tours with some friends and we were going down a fairly good hill. I was having so much fun I took my hands off the bar and did a on the bow of the Titanic move (look ma', I'm flying)...nobody was around me so I wasn't endangering anyone. At the bottom of the hill I was surprised when my friends said something about how they wished they could do that. It took me a second to realize they meant ride with no hands. I guess I just thought everyone could do that. I've also gone climbing and done some repelling...so I'm not the kind that minds taking a few risks. But I do think time will take care of it.
As we must account for every idle word, so must we account for every idle silence." ~Benjamin Franklin