First time I heard this one......

[Kingodaroad]

Friend has 05 Sportster Custom and went to local HD dealer to buy stuff needed for fluid change. I suggested at minimum SYN3 and even Amsoil as the dealer stocks it. He gathered up what he needed and went to parts counter for the oil filter. Parts rep pulled the oil filter and noted my friend had SYN3 for the oil change. I listened as the parts guy told him it was bad to run synthetic oil or fluids in air cooled motors. He said the synthetics make the motor run hotter because the stuff did not dissapate heat and actually retained heat causing motor to run hotter. I told parts guy you can check motor temps and the syn does run cooler. He says it looks that way because we are checking the temp at the oil tank and not in the engne. I had to walk off. Of all the homespun theories I've heard on syn oils that one got me.

[msocko3]

The Parts guy proves that some folks just shouldn't breed.

[DBotkin]

He must have been confusing synthetic oil with marinara sauce. Now, THAT stuff stays hot forever.

[ktwillys]

come on guys.....

did you actually read the lable...

good grief... your friend must have been buying the Syn that has the Tabasco additive


come on pay attention...........

[dynarule]

Not to be leaning one way or the other,but this may be a good topic. What would be the difference between SYN and DINO as far as absorbing the heat from the engine to cool it? Does syn show a lower temp in the oil because it doesnt soak up as much heat giving a false idea of running cooler? Remember now this is not an attack on syn cause i am using it myself right now. But i think this may be a valid question.

[nightrob]

"Synthetic Oil Explained

Whether it's evil stuff or good stuff depends on who you talk to. And a lot of what you hear from backyard mechanics is rumor and myth. Myth # 1 is the claim that you don't have to change Synthetic oil as often as regular motor oil. Remember when Mobil 1 said you could go 25,000 miles between oil changes with synthetic oil? Notice they haven't said that for a good number of years? Keep that thought on the back burner for now... Myth #2 is that synthetic oil causes oil leaks. In this article I'm going to try to dispell these myths for you with the cold hard facts about the differences and similarities between dino vs. synthetic oil.

Let's talk first about what "dino" oil is (Dino is short for Dinosaur, which is when it started forming). Dino oil is created from something called "Base Stock". Base stock what the oil companies get after they have processed the crude oil that comes from the ground. From there, additives are combined with the Base Stock, to create our motor oil. There are 7 main additives which include anti-foaming agents, anti-corrosion, etc, etc. At the molecular level, dino oil contains molecules of varying sizes. Imagine the floor of a gymnasium covered with basketballs, baseballs, volleyballs, and beach balls. Now imagine that all those different size "balls" are moving around, flowing past the floor. Every time a ball surface contacts the floor surface, the ball absorbs heat from the floor. That is how oil removes heat from your engine components, from surface to surface contact.

Now imagine the same gymnasium floor covered in uniformly sized golf balls. Smaller, more uniform molecules can absorb more heat from a surface, because there are more of them AND they have a larger surface to volume ratio which means they have more surface area contact. That's what synthetic oil is. A man-made "Base Stock", where all the molecules are the same size, and smaller than those in dino oil. Better heat transfer, better lubricating properties, and a lot wider temperature range without breakdown, are now obtained.

Myth #1 debunked

Oil does not break down under normal use. This is true of both dino and synth oil and is also the reason why you take oil to the Recycling Center and not the trash dump. So if oil itself doesn't ever degrade, why do we have to change it? The answer is twofold: additives and contamination. It will probably surprise you to learn that synthetic oil has all the same additives that dino oil has! The additives in oil DO break down, which is part of what necessitates oil changes. The other reason for regular oil changes is that with use, motor oil becomes contaminated (dirt, water, acids, etc). Using synthetic oil does not protect against either of these problems, which is why you CANNOT go further between oil changes when running a synthetic. You should still change your synthetic oil at the same intervals as you do with dino oil. Anyone want to guess how many claims Mobil 1 had to pay to people that were going 25,000 miles between changes?

Myth #2 debunked

Synthetic oil causing oil leaks is another commonly spread myth. The truth of the matter is that if all your engine seals and gaskets are in good condition, synthetic oil will NOT leak in your engine. The myth started because on occasion, an engine will leak with synthetic oil, but not dino oil. The reason for this is that the smaller molecules of the synthetic are able to get past very small crevices, where the larger molecules of dino oil cannot. But this does not mean that the synthetic oil has caused the leak, it simply has "discovered" an infant leak, and regardless of what oil you are running, this infant leak will eventually grow to a size that will allow dino oil to occupy and pass also. Synthetic oil has not been shown to deteriorate engine seals or gaskets. It is not some evil solvent that will break down sealant, or anything like that. Like was said earlier, it is just a man-made base stock, that is uniform and smaller in molecule size than dino oil. Nothing more, nothing less.

ADVANTAGES OF RUNNING SYNTHETIC OIL in AIRCOOLED ENGINES
So if you are asking yourself "What's the point of running synthetic oil, if you can't change it less often?" Here's your answer in a nutshell.

Since synthetic oil has better heat transfer qualities than dino oil, your internal engine temperatures will be lower. Things like bearings, especially, will not operate at as high of a temperature as a result. The wider range of temperatures that synthetic oil can withstand is well suited for the air-cooled VW engine. With head temperatures normally between 300-350 degrees, synthetic will not breakdown while lubricating the valvetrain components at the heads. The better lubricating properties of synthetic in general will lead to a longer engine life as well. On average, when synthetic oil is run in an air-cooled VW engine, head temperatures stay the same, but engine oil temps reduce by anywhere from 10 to 15 degrees. This is in engines that have all the correct cooling tin in place, and are not suffering from overheating to begin with. Important note: Do not run synthetic to fix a hot running engine. Find the real reason it's running hot, and fix it!

Another benefit is that since synthetic oil is man-made, it can be tailored to suit a wider range of needs. Synthetic oil is now being made is such weights as 5w50, and 0w30, weights that are not possible to achieve with dino oils."

courtesy of aircooled.net

[george douglas]

Originally Posted by nightrob

"Synthetic Oil Explained

Whether it's evil stuff or good stuff depends on who you talk to. And a lot of what you hear from backyard mechanics is rumor and myth. Myth # 1 is the claim that you don't have to change Synthetic oil as often as regular motor oil. Remember when Mobil 1 said you could go 25,000 miles between oil changes with synthetic oil? Notice they haven't said that for a good number of years? Keep that thought on the back burner for now... Myth #2 is that synthetic oil causes oil leaks. In this article I'm going to try to dispell these myths for you with the cold hard facts about the differences and similarities between dino vs. synthetic oil.

Let's talk first about what "dino" oil is (Dino is short for Dinosaur, which is when it started forming). Dino oil is created from something called "Base Stock". Base stock what the oil companies get after they have processed the crude oil that comes from the ground. From there, additives are combined with the Base Stock, to create our motor oil. There are 7 main additives which include anti-foaming agents, anti-corrosion, etc, etc. At the molecular level, dino oil contains molecules of varying sizes. Imagine the floor of a gymnasium covered with basketballs, baseballs, volleyballs, and beach balls. Now imagine that all those different size "balls" are moving around, flowing past the floor. Every time a ball surface contacts the floor surface, the ball absorbs heat from the floor. That is how oil removes heat from your engine components, from surface to surface contact.

Now imagine the same gymnasium floor covered in uniformly sized golf balls. Smaller, more uniform molecules can absorb more heat from a surface, because there are more of them AND they have a larger surface to volume ratio which means they have more surface area contact. That's what synthetic oil is. A man-made "Base Stock", where all the molecules are the same size, and smaller than those in dino oil. Better heat transfer, better lubricating properties, and a lot wider temperature range without breakdown, are now obtained.

Myth #1 debunked

Oil does not break down under normal use. This is true of both dino and synth oil and is also the reason why you take oil to the Recycling Center and not the trash dump. So if oil itself doesn't ever degrade, why do we have to change it? The answer is twofold: additives and contamination. It will probably surprise you to learn that synthetic oil has all the same additives that dino oil has! The additives in oil DO break down, which is part of what necessitates oil changes. The other reason for regular oil changes is that with use, motor oil becomes contaminated (dirt, water, acids, etc). Using synthetic oil does not protect against either of these problems, which is why you CANNOT go further between oil changes when running a synthetic. You should still change your synthetic oil at the same intervals as you do with dino oil. Anyone want to guess how many claims Mobil 1 had to pay to people that were going 25,000 miles between changes?

Myth #2 debunked

Synthetic oil causing oil leaks is another commonly spread myth. The truth of the matter is that if all your engine seals and gaskets are in good condition, synthetic oil will NOT leak in your engine. The myth started because on occasion, an engine will leak with synthetic oil, but not dino oil. The reason for this is that the smaller molecules of the synthetic are able to get past very small crevices, where the larger molecules of dino oil cannot. But this does not mean that the synthetic oil has caused the leak, it simply has "discovered" an infant leak, and regardless of what oil you are running, this infant leak will eventually grow to a size that will allow dino oil to occupy and pass also. Synthetic oil has not been shown to deteriorate engine seals or gaskets. It is not some evil solvent that will break down sealant, or anything like that. Like was said earlier, it is just a man-made base stock, that is uniform and smaller in molecule size than dino oil. Nothing more, nothing less.

ADVANTAGES OF RUNNING SYNTHETIC OIL in AIRCOOLED ENGINES
So if you are asking yourself "What's the point of running synthetic oil, if you can't change it less often?" Here's your answer in a nutshell.

Since synthetic oil has better heat transfer qualities than dino oil, your internal engine temperatures will be lower. Things like bearings, especially, will not operate at as high of a temperature as a result. The wider range of temperatures that synthetic oil can withstand is well suited for the air-cooled VW engine. With head temperatures normally between 300-350 degrees, synthetic will not breakdown while lubricating the valvetrain components at the heads. The better lubricating properties of synthetic in general will lead to a longer engine life as well. On average, when synthetic oil is run in an air-cooled VW engine, head temperatures stay the same, but engine oil temps reduce by anywhere from 10 to 15 degrees. This is in engines that have all the correct cooling tin in place, and are not suffering from overheating to begin with. Important note: Do not run synthetic to fix a hot running engine. Find the real reason it's running hot, and fix it!

Another benefit is that since synthetic oil is man-made, it can be tailored to suit a wider range of needs. Synthetic oil is now being made is such weights as 5w50, and 0w30, weights that are not possible to achieve with dino oils."

courtesy of aircooled.net

Nice post, but I do need to point out that syntheitc oils like Amsoil and Mobil are by design able to go longer between oil changes. Mobil has one product designed for 15,000 miles and Amsoil has one for up to 35,000 miles. The reason this can be safely done is through additive chemistry. Put cheap additives in and you get cheap service life period. I have personally done extended oil service life for going on 29 years now and have never worn anything out yet. I have thousands of customers doing the same thing with equal results. Also keep in mind that most synthetic oils sold by the major oil companies are not man made oils as stated in your post, but simply 100% petroleum oils to start with and can legally called full synthetic by decree of a judge along with the blessings of big oil. These are good oils though so I am not bashing them, but I feel they could be sold at a lower price than the real syntheitc oils like Mobil, Redline, Royal purple, Amsoil, and a few others.
george

[ktwillys]

great post..
always a good read..

syn will lower your temps by 15 to 20 degrees...

this I know for a fact..

so do a lot of others..

[fatty239]

Originally Posted by ktwillys

syn will lower your temps by 15 to 20 degrees...

this I know for a fact..

so do a lot of others..

[TriLs]

Originally Posted by nightrob

"Oil does not break down under normal use. This is true of both dino and synth oil and is also the reason why you take oil to the Recycling Center and not the trash dump. So if oil itself doesn't ever degrade, why do we have to change it? The answer is twofold: additives and contamination.

Thanks Rob for a great post!

One question:

The so-called "volatile fraction" of the oil that gradually dissipates out the breather with use and, if not caught in time, will lead to varnishing is composed of solely additives, then?

This has always puzzled me...

Thanks again!

Tri

[doc ock]

Originally Posted by dynarule

Not to be leaning one way or the other,but this may be a good topic. What would be the difference between SYN and DINO as far as absorbing the heat from the engine to cool it? Does syn show a lower temp in the oil because it doesnt soak up as much heat giving a false idea of running cooler? Remember now this is not an attack on syn cause i am using it myself right now. But i think this may be a valid question.

Well there is a scientific fact to this. Heat travels in one direction, from hot area to cold. Heat is drawn out. If you have two items one hot and one cold the heat will be drawn from the hot item to the cold item. So as the oil is circulating in the motor the heat is drawn out of the motor to the oil. I guess you could have high oil temps but lower engine temps. We always look at oil temps to see if the engine is runnning cooler. Think of it like this. If you put your hand on a hot stove you get burned because the heat is drawn to your hand, but you cannot cool the stove down with your hand.
Please do not try this at home, read about it.

[Kingodaroad]

I'm glad I posted that at the top. A lot of good information and discussion came from it. Thanks for the oil lesson! We have a lot of intelligent folks here. I tell friends to log on and join as they can get about 50 yrs of information in less than 5 minutes.

[doc ock]

I guess we need a lab to figure out this theory. Would be interesting. Cooling factors of Synthetic vs Dino.

[dynarule]

Originally Posted by doc ock

I guess we need a lab to figure out this theory. Would be interesting. Cooling factors of Synthetic vs Dino.

I dont have an oil temp gage but an easy would way to do this would be to use one of those neat laser temp guns and and take a temp of the jugs on the engine, once with syn then once with dino on the same bike in the same outside air temp and see what kind of real difference there is on the engine rather than oil temp. If I had one of those temp guns I would be willing to do this on my scoot and keep good logs on it to see.

[YankeeBob]

So I don't want my bearings to skate? I want them to "dig in" and spin? Even though skating is running virtually friction free??
Let's see....no load, no friction, means shorter life??

What am I missing here?