However, I recently had a neighbor kid come over asking for some bike maintanance - I do it for free for the local folks and all the kids know where to go when their bikes are out of whack.
Anyway, I was out of chain lube and the kid's chain was dry as Nevada, so I took my oil can that has some low viscosity motor oil in it. I find this oil works very well for most general lubrication needs.
So, anyway, I lubricated the chain with the motor oil.
The question came to mind; "why not use good motor oil for chain lubrication" It has good cling, it is penetrating, and it is a good lubricant.
Is there any reason NOT to use motor oil on a chain?
I've also used it on my relatives bikes when I don't have bike lube on hand. It's a great lubricant but you'll find it will be more messy than a dry type bike lube. It will attract dirt but the wet type bike lubes will too. Just be sure to wipe off as much excess as possible. Other than that there should be no problems.
Like a previous poster mentioned it will attract dirt like a magnet. If you want a cheap lube to use on the neighbor kids bikes that will lube well and not attract the dirt like motor oil try TriFlow, you get a big can for little cost.
The standard recipe for "home brew" chain lube is One part motor oil and four parts mineral spirits. Synthetic motor oil is preferred. Paint thinner, kerosene, or diesel fuel could substitute for mineral spirits.