chain loob (intentionally misspelled, because i saw it spelled this
Posted: Fri Dec 10, 2010 10:51 am
As an eternal skeptic, and a fan of Science!(tm), I tend to over-think things. I also like to take stuff apart and see how it works. A few years back I decided to take a long hard look at sealed chains. I had purchased a chain that was a few links too long, so after cutting it, I had some links to play with.
After taking the links apart and examining the inside, sure enough... there's a nice thick grease inside. The rollers are essentially just that: rollers. There's no seal at the edges of the rollers, but they are cut very smoothly and fit snugly against the side plates.
So, given that... logic will say that 99.9% of your chain lube is wasted. The parts of the chain that see the most stress and motion are INSIDE and lubricated by that thick, sticky grease inside. O- or X-rings keep that grease inside. My brain says that as long as you keep the rings in good shape, the places where friction would occur are lubricated. The rest only serves to present a water-repellent film to keep the side plates, etc from rusting.
Of course, you'll want to remove the grit to keep it from chewing up the rubber rings, and keep them nice and moist. A thin film on the rollers probably isn't a bad idea either, but they're smooth, and they contact a smooth part of the sprocket so friction will be low there as well. The only other place that I can see that the internal lubricant could potentially leak out is between the roller and the internal side plates. The fact that the surfaces will wear to a near perfect fit is what keeps the grease from squirting out there, in my estimation.
If all of the above is true you should be fine if you simply keep the o-rings clean and moist. Whatever lubricant you use should:
* Repel water
* Moisten o-rings
* Fail to attract or hold grit
* stay in place for a reasonable amount of time
When I got a wild hair to replace my KLR's chain at 17K a few months back (it didn't "need" it, but I did just to be on the safe side) I took the links apart and examined them.
The pins looked beautiful. Most of the internal grease was gone, but the surfaces were still oily to the touch. The pins were not so much worn as polished to the naked eye. Comparing the diameters with a pair of calipers, there was very, very little measurable wear. If you ran your thumbnail down the pin, you could feel the slightest groove where the side plates contacted the pin. Whipping out my son's EyeClops video microscope, you could actually see the wear... but it was very minor.
So, based upon my observation I just clean and lube the o-rings, then wipe the rest of the chain down with a rag with some gear oil on it. I don't get much "fling". I don't have a set interval that I maintain it, but whenever it has been wet, or gritty or looks a little dry I'll do it.
This has worked well for me.
-Jeff Khoury