Heavy Chains and Padlocks
Pros: They’re practically bomb-proof and the best option for all day or all night security. (The Kryptonite Fahgettaboudit or New York Chain are the closest to theft-proof that you can get.) Five-foot and three-foot lengths give you a variety of lockup options.
Cons: They are really heavy to carry around. You can’t lock both wheels and the frame to the same object; to do so, you have to remove one wheel.