What is a good way to weatherproof a bike outside So I've been going to college over in Michigan for the past few months, and I've always been worried about the condition of my bike. Back at home, I used to keep it in a shed to protect it from the elements. But now that I live in a dorm, my only option is to keep it outside on a bike rack; and it's already showing signs of rust. I tried bringing it into my room before, but space is VERY limited and I still ride very often between classes and on long trips. Does anyone have any ideas on how I could protect my bike from the harsh weather outside?
Just leave it alone. 

If you have a steel bike and theres gaps in the paint, the rust is likely cosmetic, but you can carefully sand and prime and paint the area. Aluminum and Carbon fiber shouldn't have this problem. 

Oil your chain regularly, and replace parts as needed -- your drivetrain will rust out quicker but that's the nature of it. Rain, snow  and salt tend to degrade your drivetrain quicker than nice conditions, but theres nothing to do about it unless you bring the bike indoors.