I use to live in Chicago while I was going to school. I got my first bike (Honda 450 nighthawk). No wind screen living on a student's income. Had to use that bike alot no matter the weather. Had to at times sit at the stop light, pull my gloves off and stick my hands on cylinder just to warm them up.
I won't ever go that cold again. But I have found that if I bundle up good then I can handle most weather. I avoid freezing temps though due to ice concerns and won't ride in snow at all.