I finally got out to ride the other day and noticed that my front brake felt funny. It didn't feel quite as firm. I rolled it around and then idled around mashing the brake and it worked fine, but you had to pull the lever in farther than you did back when it was warm. Is this normal for cold weather or do I need to bleed the system or just change the fluid completely?

 

How cold is cold? are we talking zub zero C or ???