Monte,
No big ones - just a lack of common sense combined with youth. In 1971 I was stationed in Germany and became friendly with a group of German motorcyclists. Come fall they told me that it snowed around there and I would not be able to ride a solo bike - I NEEDED a sidecar. They found one for me in a junk yard and after "restoring" it with a spray can of paint I prooceeded to ride all winter and ship it home.
I still have the hack but when it snows I grab the car keys rather than a helmet. Perhaps wisdom came along with all these gray hairs. ;-)