This was on bike romour a few years ago from one of Shimano’s main tech gurus, Nick Murdick,
BikeRumor: What is Shimano’s official stance on the chain lube that comes stock on a shimano chain? Is it actually a lube, or a grease? And is it best to leave it on until the chain gets noisy and relube, or strip it right away and relube before riding?
Nick: So that brings us to lubrication. I mentioned that the chain wears because of friction as the chain moves to wrap around a gear. Well, that friction is reduced if there is lube on the chain. If there is dirt mixed in, the lube makes a bigger difference in reducing friction. If there is water mixed in, the lube helps displace the water. The grease that comes on a Shimano chain is applied at the factory to the individual pieces before the chain is assembled. The grease does a better job of reducing friction than aftermarket chain lubes and it lasts longer. The main reason we use liquid chain lube, whether it is one that stays liquid or a dry lube that has a solid lubricant in a liquid carrier (like a PTFE lube) is because we need to get the lube on a part that is not accessible without disassembling the chain. So the best thing to do when installing a new chain is to leave the factory grease on, not apply any other lube, ride until it wears out and then start applying liquid chain lube. In dusty conditions you can wipe off the outside of the new chain with a rag that is wet with a gentle degreaser to keep dirt from sticking to the grease. The factory grease also keeps the chain nice and quiet. After soaking a chain in degreaser and then lubing the chain with liquid lubricant the chain gets noticeably louder.