WD-40 is a poor lube. I recall a test of motorcycle chains where they built a test rig to run short chains using different lubes. WD-40 was the worst. It caused more wear than no lube at all. WD-40 is good for cleaning chains and for getting water out of the chain after riding in the rain.

I use homebrew lube which is 1/3 30wt oil (I use left over synthetic two-stroke engine oil from motorcycle racing) and 2/3 mineral spirits. Every couple rides I apply lube and wipe the chain clean. It takes less than a minute.