I don't know, but I bet it is a marketing stunt.

For instance, in Norway they sell cooling fluid to have in your radiator in the summer and antifrost fluid in the winther, they are labelled differently but contain the exact same crap. Same shit different wrapping. This is how they aquire more shelf space, make their product seem unique and superior, and hence they sell more... but don't take my word for it.

No, the cooling liquid is also a corrosion protector, very necessary for the engine. You can run an engine with just plain water, but in the long run it will corrode and gunk will build up in the cooling system.

My comment was a bit misleading... yes, the cooling chemicals are better than water for the reasons you say. What I ment to say was that it is the exact same product (chemical composition) winther and summer, they just call it by different names in summer and winther, to get you to change what you have and buy more... I didn't mean to say the product was crap, although it was in fact the exact thing I said... what I meant that the marketing is crap... or ingenious (which ever way you want to see it)

Synthetic oil is designed for use in modern hi tech engines with tight tolerances, mineral oil is not good for them. Old engines were designed to run on mineral oil, not synthetic. If your engine is used to running on mineral oil conventional wisdom is not to suddenly start running it on synthetic as it will piss oil everywhere! someone earlier mentioned about the deposits, well they fill up the gaps in your gaskets etc, using a mineral oil can remove these as part of it's cleaning action and you end up leaking everywhere. It's a bit like when you flush your rad out, and then really regret it afterwards 'cos it leaks everywhere. Older engines don't have fine enough tolerances to use synthetic oils. (by that I mean like old landy or TLC engines derived from a bus!)

Andy
TLC H60
landrover 101 ambie/camper
1968 morris minor traveller

The diference is in the additives. Most cars run a dry clutch and special, more¨slippery additives in the oil. Most motorcycles have a wet clutch, with the exception of BMW, Harley Davidson and i think Moto Guzzi. Here the theory is that the clutch will not preform properly if you use car oil with the additives, but only in theory. I know a guy with a KLR and he only uses car oil, never a problem with the clutch. I wonder if anyone here could contribute to this specific topic...anyone have a clutch fail due to using car oil??

Second after all lawyers, marketers is the professional group the world would be better without. They should all be sunk to the bottom of the ocean, together with their synhetic oil and whitening chewing gum... exept me ofcourse http://www.horizonsunlimited.com/ubb/smile.gif

oi wheelie, see you in court mate. http://www.horizonsunlimited.com/ubb/smile.gif

a lawyer

There's a lot of good advice here, but I don't really understand why you all refer to mineral as dino. Synthetic is dino as well, just the manufacturing process is more complicated.

There is no real difference between the oil in mineral and synthetic oils. Remembering back to my carbon chemistry, oil is simply long hydrocarbon chains (as opposed to short hydrocarbon chains, like in petrol). What makes the difference between the two oils is the way they are manufactured and this in turn effects the lengths of hydrocarbon chains present.

Mineral oil is refined from crude in a 'ground up' separating process. This results in an oil that has a greater distribution of carbon chain lengths.

Synthetic oil is created in a ‘top down’ approach from joining smaller hydrocarbons that ensures that the chain lengths are a lot closer in length.

That is the only difference in the oils. However, this leads to many differences in how machines are designed and how the oils are formulated. Because the composition of synthetic oils can be more closely controlled, engineers can now design bikes to closer tolerances based on the assumption that a certain type of oil will be used. This effects things like operating temperatures, gasket pressures and piston clearances.

And then, because new bikes are designed with synthetics in mind, any additives that are invented to stretch the life of the oil, clean the engine, increase the operating temperature range, etc. are added to the synthetic oil. To an engineers mind, putting your new additive into an inferior mineral oil would just be a waste of time.

So, as far as bikes are concerned, the only thing that matters is that you closely match the manufacturers specifications regardless of mineral or synthetic. However, if for example you take a new bike from synthetic to mineral, you will have changed the required oil change period (eg, mineral will wear out quicker than synthetic). What to can only really be worked out by the manufacturer, however it would probably be safe to, say, half your oil change period when using mineral.

Also, changing oils willy-nilly is not a good idea. With two different oils in your engine, there is a chance that a difference in viscosity or weight will cause the oils to circulate differently than designed for. E.g. the lighter oil can sit up in your frame (I’ve got a frame cooled XR) and not circulate round the engine. If using a different oil, I’d recommend a full oil change.

Finally, car oil will make a wet clutch stick, I’ve seen it. Maybe it works in a road bike running at constant speeds, but it seems to shag a trailbike clutch pretty damn quick.

An Engineers two cents,
Matt

On the road in Mexico, I carry a bottle of WalMart oil for the occasional little top up and when it comes time for the oil change I´ll go with whatever is available in the right viscosity range and API classification. Like Grant says any oil will do . Expensive oil MAY be better than cheap oil , but cheap oil is always better than NO oil. In all the years I´ve been riding I have never lost a motor due to it running on the "wrong" oil. I did once strip second gear in a Suzuki T500 because the output shaft seal let the oildrain down-no oil !
"Dino(saur) oil" is a misnomer because the crude oil is derived from ancient marine sediments and maybe comet debris and was already in the substrates before the age of dinos.

Sounds to me like some engines can handle differnet oils and some can't. Again, it comes down to YOUR specific bike for a recommendation.

Ironically, I had a hard time finding 10W-40 mineral oil in Central Asia...all they had was synthetic!

My Transalp seems to run on anything I put in. I think I will try the olive oil suggestion next, can I use the Italian stuff even though I have a Japanese bike?

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Dave
www.mototrekker.com

You should be able to do that. In the owners manual of my old RD250 I remember reading that if you want to use vegetable-based oil in the gear box you had to clean and rinse it out first, because the two together turn into a caoutchouk-like solid mass. http://www.horizonsunlimited.com/ubb/wink.gif

What a mess...

Hmm, thanks for many good and well founded answers. I'm getting wiser here.

Here is another common allegation out there: The word is that you cannot mix types of oil e.g. syntetic and mineral, partly because it will make the cluch slippery (which is already mentioned here). Then what about semi-syntetic oil - isn't that half syntetic half mineral? Or is is more complicated than that?

by chance i asked that question a week ago at my lokal honda dealer and acordig to them you can safely mix sythetic and half-synthetic oil but not mineral and half-synthetic or fully synthetic, i didn't ask why not. if the above turns out to be wrong i'll let you know, just chanced the oil on my ntv 650, and mixed 0.5 liters fully synthetic (with i had left standing) with 2 liters half-synthetic, so i'll will find out

I thought the point of using half synthetic was that you could mix it with either full synthetic or mineral oil.

If the oil is half synthetic, what is the other half made of???

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Dave
www.mototrekker.com