Bikers I've known -- my husband, and a guy I used to date -- recommend always wearing leather, even if it's hot... it keeps your skin off the pavement. My husband always bitched about helmet laws, but his last bike wreck... you shoulda seen that helmet. If he hadn't been wearing it, I'd have been a widow. He left a good bit of the meat of his left lower leg and left asscheek on the pavement, and got 3 broken bones in his foot from the steel-toed boots he was wearing... but without them, he probably wouldn't have had much of a foot left. And that helmet most definitely saved his life.
Andria