I use a "home-brew" of 1 part Mobil One (10 - 40) and 3 to 4 parts of mineral spirits. Most of the mineral spirits evaporates and leaves the oil. I've never failed to get at least 5000 miles before any 1 foot interval of chain has stretched to 1 1/16 inches. If you let it go to 1 1/8 inches you may get to buy a new cassette with the new chain. All of this refers to road bikes.