Originally Posted by
Joe Minton
Thick oils, like Chain L, Tenacious, etc. will not run out of a chain. Their enhanced surface tension, given the clearances inside a chain, trumps gravity. They stay put.
My Poulan bar oil is about a 40W but has a surface tension enhancement additive that makes it really 'suck'. I could leave my bike sit for a couple of months and the chain would still have a full thickness of oil between all the moving parts.
BTW: That 'full thickness' is a pretty good barrier to particles of dirt.
All we can do is to try and keep the grit out of the moving parts. An enclosed oil bath is an improbable best. A full chaincase is an obtainable best. Motorcycle chains now run the pins and bushing in multiple 'chain cases' in the form of O-ring chains. Chain L, Tenacious and similar special oils do the next best thing by using their thickness and extra surface tension to act as a barrier to the entry of grit.
Put on thick, sticky oil, let it soak in for a quarter hour so then wipe all that you can off the exterior of the chain -- this is the best we can do.
Joe
I have used Tenacious oil in the past. It does indeed run out of the chain. I could wipe the chain and still see threads of oil forming between the jockey wheel and the chain. Consider that if you have to wipe the chain constantly to keep from having oil on the outside of the chain, where does the oil on the outside of the chain come from? If you can get the oil to flow into the chain, there is nothing there to keep the oil from flowing out. That's the way fluids work. There is nothing magical in these heavy oils that keeps them in place.
As for the idea that "thick oil remains the best lube for chains", according to whom? Lubricant is basically unnecessary to improve efficiency in chains according to this
Johns Hopkins study. One of the more interesting bits of the news release is
"The role of the lubricant, as far as we can tell, is to take up space so that dirt doesn't get into the chain," James Spicer says. "The lubricant is essentially a clean substance that fills up the spaces so that dirt doesn't get into the critical portions of the chain where the parts are very tightly meshed. ...On the road, we believe the lubricant mostly assumes the role of keeping out dirt, which could very well affect friction in the drive train."
Oils, by their very nature, don't work to keep the dirt out. Particles of grit that falls on the oil on the outside of the chain...even just a little...will become entrapped and move through the oil to the insides of the chain. It doesn't make silicon carbide (that's a different material that requires chemistry to make) but it does make a grinding paste. I've washed plenty of chains when using Tenacious oil and could find grit and magnetic metal bits (iron) in the wash liquid. I could even hear the grit in the chain. I don't have that experience with wax based lubricants.