WD40 and only every other ride?
I wonder if there's another element to all this - I have a sit-up-and-beg bike I go into town on, it's a single sprocket, Nexus affair... I lube that about once a month if that. Never had any gripes about running dry, except when I've forgotten to lube it for many months. I've used the same gunge on it as any other bike. Never yet used WD40 on it though.
But on any bike with derailleurs, I really notice lube drying out, so much so that I re-apply it every ride and notice if I don't. What's needed here is a blind test - it might turn out I don't actually notice the difference, but "I could swear that WD40 doesn't quite do it"... However that could also be said of all you guys that swear by one or other type of lubricant too!
ljerams - please refer your complaint to my solicitor (pure sarcasm)... seriously though, it's a discussion about chain lube, nothing more serious, so calm down mate! I take on board your suspicion of modern lubricants. There! I love you really!
"I have never replaced a chain for years" - neither have I, so I can't be doing that much wrong, but I was hoping to have less removing the gunged up black paste that gathers around the chain and rear mech. If 3in1 and sewing machine oil does it then maybe that's what I'll use! I'm nether overly skeptic nor anxiously hoping for the next magic formula but I was perhaps naively hoping that fancy modern stuff would be better than the old beef dripping.
"The trouble is that oil continues to ooze from inside the chain to the outside in use after you have wiped off the excess, so it does make a difference what sort it is - in terms of runniness and stickiness."
OK - and your recommendation was Prolink. So I'm narrowing it down - the right viscosity is more important than fancy additives, since on average I don't see that opinions go overwhelmingly for or against modern fancy stuff. So thank you all, even ljerams, for your helpful comments. (sarcasm-free zone!)