I know one mechanic that takes chains off every few months, cleans the sprockets and soaks the chain in half Castrol Superclean concrete cleaner and half water, hangs it up to dry for awhile, then sprays WD-40 on the chain to dry it more (WD-40 might damage O-rings if left on by itself for hours). Then right after he soaks the chain overnight in a pan of Amsoil synthetic gear lube. He uses the BelRay Superclean chain oil spray the rest of the time. He does this for street bikes and for motocross racers. He uses a clip-type master link for bikes with 60 horsepower or less, and uses a new clip every time he puts the clip back on.