On its own, the cold poses no mechanical threat to your bicycle other than reducing the battery life of your electronic devices. If you need to store your bicycle in a cold shed or garage, it's the humidity and the changes in temperature that can cause problems. If your storage area is damp, over time your bicycle will begin to corrode. Additionally, the repeated expansion and contraction caused by freezing and thawing may cause bike parts to loosen somewhat. The freeze-and-thaw cycle can also create cracks in your bike’s finish.