If you've got a bike with steel frame or parts....DON'T LEAVE IT OUTSIDE. I had a Nashbar MTB that I left out under the deck, and it was never the same after that. Lots of the components rusted out faster than you could turn your head. Most of that goes to the fact that it was an entry-level MTB, but still. Salt spray in the air can do a number on your bike....take it indoors when you're not riding it.