Used oil for chain lube

[punyXpress]

A while ago, graphite oils & greases were all the rage - isn't that the ' black ' in used oil?

[jambo]

Originally Posted by punyXpress

A while ago, graphite oils & greases were all the rage - isn't that the ' black ' in used oil?

I'm afraid the black in used oil is the suspended by-products of combustion. Carbon deposits give the black colour I think.


Jambo

Originally Posted by jambo

I'm afraid the black in used oil is the suspended by-products of combustion. Carbon deposits give the black colour I think.


Jambo

I concur. Which make me sad a little because until I run the engine with fresh oil in it, I had red oil. Looks quite cool.

I have no issues with using used oil, especially when it is an expensive synthetic. My logic goes something like this. If the oil is so spent that it is not capable of protecting the chain for the very brief period that it will remain attached, then that is the least of my problems - ie WTF was it doing in the engine for so long! Filters get down into the 8-25 micron range (don't throw the old filter into the drain pan) which is absolutely miniscule in comparison to what the road will throw at it. Last but not least, even new oil will end up a shade of black after it has been run across the chain, heated and mixed with road grime and brake dust...

I wasn't going to reply to anymore posts about this but: You call that logic? ;o)

You just do not know what is in used engine oil.

If you use it all the time, it is there for the life of the chain and sprockets, not some 'brief' period,

Used engine oil plus the 'heating and mixing with road grime and brake dust' is just maybe a tad worse than starting off with clean oil?

Have you ever felt how skinny used engine oil feels, compared to fresh stuff?

[jambo]

Originally Posted by ejohnh

I wasn't going to reply to anymore posts about this but: You call that logic? ;o)

You just do not know what is in used engine oil.

If you use it all the time, it is there for the life of the chain and sprockets, not some 'brief' period,

Used engine oil plus the 'heating and mixing with road grime and brake dust' is just maybe a tad worse than starting off with clean oil?

Have you ever felt how skinny used engine oil feels, compared to fresh stuff?

I feel to some extent we're going round in circles. I think it's unlikely I'll convince you otherwise which is fine. The hot oil coming out of an engine is very thin due to it's temperature, once it's at ambient I've not noticed it to be any thinner than new oil.

Several people have used old engine oil to get 40-50,000 miles from a chain. Maybe it's not as perfect as new oil, but modern bikes like the Z750 go 6,-8,000 miles between changes of oil, and the same stuff goes in the SV or ZX6. Oil is designed to hold the by-products in suspension away from the components they touch.

Short answer is cheap car oil, chainsaw oil, or new scottoil's not expensive, if you're in anyway concerned simply use that, it's not the wrong thing to do, but I remain unconvinced used engine oil is a poor lubricant.

Jambo

The tolerances of a chain are nothing compared to an engine so its "clean enough" however a dual weight oil is going to be too thin to be used on a chain anyway so its a bad idea for that reason only.

Yes, I wasted my first post on that!!!

Originally Posted by ejohnh

I wasn't going to reply to anymore posts about this but: You call that logic? ;o)

You just do not know what is in used engine oil.

If you use it all the time, it is there for the life of the chain and sprockets, not some 'brief' period,

Used engine oil plus the 'heating and mixing with road grime and brake dust' is just maybe a tad worse than starting off with clean oil?

Have you ever felt how skinny used engine oil feels, compared to fresh stuff?

I am fully aware of the contents of used oil. I am yet to see any damage to a chain caused by contaminants. The brief period that I refer to is the time an individual drop spends on the chain - talking a couple minutes. It makes sense to use only new oil, but having had 50k out of chains on both new and used oil it has been hard to see the difference. If the oil is so spent that it has sheared or depleted its entire additive package (ie become "skinny") and has become entirely useless then I have to ask the question, "what the hell was that oil still doing inside the engine?" The oil change was a bit too late.

...

Hi Black,

Check your manual to see what Suzuki recommends for the chain.

Cheers

Oddly, I have looked in the repair manual for what is recommended on the chain, but not for the engine (only had my bike for about 6 weeks now). Says use a heavy weight engine oil (30wt or higher) for the chain. Guess I should ask whats recommended for the engine before I post, eh?

Originally Posted by MattCo

Hi Black,

Check your manual to see what Suzuki recommends for the chain.

Cheers