|
|
|
General Oil Information
I am, by no Means, a Chemist. What I’ve learned about oil is from trial and error and by research looking for the best oil or oils that would be best suited for my purposes both in my cars and in my motorcycles. Also, a lot of my research came about by searching for good suitable 'Non Motorcycle Specific Oil. Along the way I had to come to understand how both synthetic & crude oils work. Due to my interest in motorcycle forums my research has expanded to even more of an understanding of oils.
Understanding The Viscosity Rating Of Oil
The question for this topic goes like this: I'm not understanding the viscosity rating right. I buy a 10W-40 oil and I've always thought that the lower number meant that when the oil was cold that it's thinner or a lighter weight, then when the oil is hot it thickens to a heavier weight. But when I change my oil this don't seem to be correct. What's the deal?
For this topic I'm going to use crude based oils for a reference not synthetic. Have you ever poured a 10W-40 oil out of a bottle when the oil is, lets say, 30 degrees? Does it pour out easier or faster than it does if the oil is 70 degrees? No it doesn't. Most all engine oils now are multi-grade, meaning multi-climate. These oils have two viscosity numbers; the low number is the oil's base number or to say its real weight. The high number is a bit more magical. Whatever the oils viscosity range is above its low number is what the polymers are doing in the oil. When you look at cold or hot oil you're seeing the different consistencies of the oil but that really doesn't have much to do with its viscosity rating. The viscosity range of an oil is more about molecules, those magical polymers.
The polymers are like small chain like coils that are heat sensitive. When cold they coil up into very small coils and when hot they stretch out or expand. This is where the term multi-viscosity comes from. This is a good thing for the oil in one aspect because the polymers help the oil to flow better through the engine parts as the engine temperature changes. When the engine is cold the polymers coil up to their smallest size helping the cold thickened oil to flow more like a thinner oil. The opposite end of this is when the engine heats up the oil consistency thins down and the polymers stretch out. In this state the polymers help the thinned oil to flow in and around the engine parts more like a thicker oil. So the viscosity numbers given for any oil isn't about what you can see but rather what you can't see. It's about better controlling oil flow within the engine.
The bad side of polymers is that they are a man made thingy that was added to fill a need in helping engines start better when they're cold. They really don't lubricate. They only help the other lubricating properties to better flow. So, the more polymers added to the oil the less oil you have and the wider the spread of viscosity the more the oil is dependent on polymers. In cars this is not so bad but in a motorcycle, where the oil also lubricates the transmission, it's not as good. Lets use Honda GN4 for example; it's 10W-40 and it's a crude oil base. 10W-40 tells us that the base oil is a 10 weight and the high number is achieved via the magic of polymers. Because of 10W-40 oils wide viscosity spread the oil is much more dependent on polymers to vary the oils viscosity. So when the polymers pass through the transmission's gears and get clipped or snipped it tends to break the oil down quicker which is referred to as the oils 'viscosity retention'. (or lack of it) As the polymers in the 10W-40 get diced up they become shorter and shorter and as this happens the magical derived number of 40 drops. This dicing and reduction in the length of the polymers means that the high number will continue to drop until the oil is at its base of 10W if left in the engine long enough.
There is a simple formula to figure the retention factor of an oil. The lower the number the better the oil should hold up for a few more miles between oil changes before its viscosity drops below an acceptable weight range for the engine. The below numbers would be based on each oil having the same quality ingredients.
10W divided by 40 = 4 15W divided by 40 = 2.7 20W divided by 40 = 2 15W divided by 50 = 3.3 20W divided by 50 = 2.5
I use Yamalube 20W-40 in my 1100 Shadow and I started using it before I really understood anything about the above formula. If you look at the above numbers you'll see that Yamalube is rated @ 2 rather than Honda's GN4 that is rated at @ 4 giving the Yamalube a little better retention. A 10W-40 oil would be a better choice for use in colder climates or even if you ride your bike much in colder weather, like below 30 degrees. Just remember it's not good for as many miles.
Keep in mind that, so far, I've been talking about non synthetic oil. The numbers above do work the same for synthetics but because of the way synthetic oil is built and not refined they have a greater retention across the board. So a higher number rated synthetic will better compare to a lower number crude based (dino) oil .
I've looked at a lot of oil bottles checking out the API service seals looking for that dreaded Energy Conserving statement. But I noticed something, it's mainly on the lighter weight oils, 5W-30 or 10W-30. The heavier the oil gets the less you see the energy conserving on the bottles.
Putting two & two together and a lot of research, I came up with this: Car manufactures used to recommend using a 10W-30 or 10W-40 oil in them. That was before the use of catalytic converters or in the early days of using them. Along in there, car manufactures changed to the lighter 5W-30 oils. It was thought by many that this was because of those tighter tolerances of the newer engines. Well, that isn't true. It's my understanding that the EPA was coming down hard on the automobile industry to clean up their car engines and to do something to help conserve energy. So, the car companies ended up passing some of this task to the oil companies.
The EPA concluded that the ZDDP (Zinc dialkyldithiophosphate) additive was causing emission problems with the catalytic converters. The oil companies were forced to reduce the amounts of ZDDP in the automotive oils and to come up with an oil that was more energy conserving even with the lowered amounts of ZDDP. So the weight (viscosity) was dropped and the ZDDP was lowered. Part of the theory of dropping the weight of the oil would allow the moving parts of the engine to move more freely. Think of it like this: if you were to swim the distance of two different swimming pools that were both the same size but one was filled with water and the other was filled with a thick syrup which swimming pool would consume the most energy to swim? It was rumored that vegetable oils were used by some oil companies to drop the base oils down to the new 5W-30 requirements. Doing this thinning does allow the engine to move more freely but the oil didn't lubricate nearly as well. A lighter oil doesn't protect an engine as well as a heavier oil does but the heavier oil causes an engine to use more energy. In an attempt to make the thinner oil do the job of a heavier oil the oil companies started developing the dreaded 'Extra' Friction Modifiers that us motorcycle owners have come to hate.
So when you are out looking at different types of oils and you look at the oils viscosity and the API service seal on them you'll notice that only the light weight oils will state 'Energy Conserving' in the bottom half of the API seal. In fact I've only found one brand that has a weight range above a 10W-30 that was listed as an energy conserving oil and it was a 10W-40. All others I found that were 10W-30 or below were the energy conserving type.
In many of the oil topics on the forum that I’ve seen or been evolved in, one thing that I’ve noticed is the confusion about the difference in synthetic oil and crude oil. Until recently I just thought of the synthetic oils as 'man made' and the crude oil as a 'product of nature' that has been refined (purified) for use as lubricates. I guess that was just a simple way for me to look at it.
I think about everyone has a pretty good understanding of crude oil but has a little less understanding of synthetic oil. Here’s my understanding of synthetic oil. Many of them now are called (PAO) Polyalphaolefin types. Mobil states that their synthetic oils are this type.
It’s my understanding that the molecules used in the making of synthetic oils do not start out as man made. The most common source for the molecules that are used in synthetic oil is derived from crude oil. I call these molecules 'Oilies'. What they do to make synthetic oil is to break down the 'oilies' and remove them from the rest of the unwanted properties that cannot be removed by refining alone. One of the benifits from breaking down the molecules this way is that it leaves the finished product much more uniform in size and it leaves the oil the cleanest possible. If synthetic oil is made from 'oilies' from crude, then what is synthetic about it?. They take these 'oilies' and use them kind of like puzzle pieces to build a base oil a certain way. They can join them together in different lengths to make a different weight range of oil. This new set or chain of molecules in the finished product does not exist in nature, so they are 'Man Made'. Building oil this way was really hard for me to understand for the longest time.
Synthetic oils, (True Full Synthetic Oils), need very little viscosity enhancers, if any, added to it to make it a 'Multi Grade Oil'. They can do that when building the new 'oilies' (putting the puzzle pieces together). In other words, the base oil is built to do what they want it to do at different temperatures unlike the dino oils which need viscosity enhancers added to it. This is the main reason that I can find for the synthetic oils ability to be more 'shear stable'. It’s not just an additive breaking down.
The classes of synthetic oils seem to be changing but most of them that are currently on the market at the time of this writing are broken down into two groups. I've already covered the first group which is the PAO's known as the 'Group IV' synthetic oil. The other type of synthetic oil is referred to as 'Group III' synthetic oil. The 'Group III' oils are basically crude oil that has been refined with the newer high tech refining. I did some Internet research about the 'Group III' synthetic oils and I found statements that said the companies that make these oils convinced some lawyers that this type of refining made the oil different enough from regular crude oil that it could be called 'Synthetic'. You may hear some people refer to this oil as 'Legally Synthetic'. One thing you'll notice is that the 'Group III' oils have a lower price tag than the 'Group IV' oils do. The price difference in the two can be traced back to the cost of refining one and building the other.
Now, here is an email I sent out to a person who I feel to be very knowledgeable about this topic, I also included his reply.
Hi M.L I know that to make a crude oil a 'Multi Grade' they add polymers (Viscosity Modifiers) to it, I got that. But, what about the synthetic oils? Some of the information I’ve found leads me to believe that 'Viscosity Modifiers' are not used in synthetic oils because the synthetic oil is made whatever multi-grade they want it to be. Right or wrong? I guess my thinking was that the base oils are synthetic (rebuilt from dino molecules (PAO's) and then the oil was pretty much treated the same as crude oil, meaning adding viscosity modifiers and the rest of the additives to it? Thanks for all your help and information. Mark
The Reply
Hi Mark, Synthetics are designed to have the right temperature characteristics. They have little or no viscosity modifiers, polymers if you prefer. The problem for dino oil is tied to refinement. Until very recently, dino oil was 15% - 25% wax and parafin. This stuff really made the viscosity thing hard to deal with, as the parafin is very thick at room temp and thins out enormously at 200. Get rid of all that and what's left isn't so bad. M.L
Some claim and even debate that synthetic oils are 'slicker' or that it's better at reducing friction vs crude oil. But the lubricating properties in the base oils used in synthetic is built from 'oilies' from crude oil. So, is it slicker than crude? I’ve said many times that if synthetic oil was really slicker than crude, then it couldn’t be used at all in an engine with a wet clutch system because it would make the clutch slip for sure.
Another debate is the belief that there is something about synthetic oil that will not allow an engine to break-in so they don’t want to run synthetic oil until how many ever thousands of miles. I think a lot of this belief comes from this thinking that synthetic oil is so great, so slick, that it reduces friction to a level that the engine parts won’t seat together. Let me ask you again, what is it about synthetic that is slicker, outside the additives that go into some of them?. From my research I can't see any reason that if you have rode your new bike with the factory or dealer installed oil until the first 600 mile service, then it's safe to switch to synthetic oil. If you're thinking about doing that, then please do some research about the pro's and the con's of going with a synthetic oil. Just try really hard not be taken in by all the marketing hype and all the mystical claims about synthetic oils.
Some think that because synthetic oils cool better that it must lubricate better. Right? That's not true as far as I can find out. It has more to do with the uniformity of the particles that make up the base oil. Crude oils are a product of nature so the particles vary a great deal in size. When the crude oil is flowing through the small oil ports and or passages in an engine the smaller particles move easier or faster than the larger ones. So the smaller ones force their way up the middle pressing the larger slowing moving particles to the side of the passage. Doing this the larger particles somewhat block heat transfer to the faster moving oil particles causing the built up heat in the metal to not transfer evenly to all the moving oil causing the engine to run a little hotter. Synthetic oils particles are more uniform because it's all man made. The more uniform the particles that make up the oil the more even the flow is of all the particles and this helps to better transfer the engines heat from the metal to the oil. A big plus in a very hot running engine, a high performance engine, or an air cooled engine. But I don't figure in the Shadow's V-Twin water cooled engines this does much of anything.
Synthetic Oils Better Cleaning
What's all the talk about how synthetic oils keep an engine cleaner? Do they really run as clean as the companies that make them claim?. For this lets go back to the reason why synthetic oil came to be. The story I came across stated that years ago the military was having trouble with getting the crude oils to work properly in some type of airplane engines at high altitudes. So the governments need for an oil that would do what they needed it to do brought about the research for a synthetic oil. The problem was with the rather pour refining methods being used at the time they just couldn't get enough of the waxes and paraffin's out of the oil. It's my understanding of that time that after refining the oil it would still have a better than 25% content of waxes. The waxes were the problem, they were causing the crude oils to thicken to much at the cold temperatures at the extreme high altitudes and then at lower altitudes where it might be hotter the oil would thin out to much. They needed a cleaner oil than could be had by refining. So came the synthetics.
Part of the reason that synthetic oil cleans so much better than crude oil is because the stuff that makes crude oil dirty isn't present in the synthetic oil. That makes the detergent additives more effective at cleaning the engine if it don't have to clean up its own mess. The oil industry has played up big time on much of the improvements that synthetic oil has over crude. But much of what we hear are really just echo's from the past, from stories of how the two oils compared then, not really now. See, over the years the refining of crude oil has gotten much better, in fact leaps and bounds better. The refining of modern crude oil is so advanced that the gap between crude and synthetic isn't nearly as wide as it used to be. Hydrocracking is one of the improvements in refining that has really closed the gap.
Hydrocracking: the process whereby hydrocarbon molecules of petroleum are broken down into kerosene and gasolene by the addition of hydrogen under high pressure in the presence of a catalyst. More about Hydrocracking
The fact is that the modern crude oils are so clean that it causes synthetic oils to lose some of it's shine. At this point I might wonder, is synthetic oil really worth its price?
What’s the deal on changing to synthetic oil And Having leaks & Rattles
There have been many reports of people switching to synthetic oil in older engines and then having problems with oil leaks developing. I've heard it's because the seals are conditioned to crude oil and the synthetic oil is so much slicker that it just slips right on by the seals. There's that slicker statement again. LOL
Well, it's not so much about the age of the seals as it is 'Varnish Build up'. Crude oils have waxes and paraffin's in them that don't get fully refined out. These waxes tend to burn and smoke and this leaves a gold color film inside the engine. I call it Dino Plating. This plating grows and fills in around the different parts of the engine. As the engine wears, the varnish fills in that space. The dino plating also forms around the seals in a way that it becomes a main sealing factor for the seals to control oil, so the seals and the plating wear and seat together. The plating also plates the gaskets leaving them to drying out or rotting, or the varnish can build up within the gasket material.
Another problem I personally dealt with in two of my car engines was after switching to synthetic oil in them and both having 100,000 miles plus was they started rattling? This don't seem to happen as often as opposed to oil leaks. I had a hard time finding any information as to why this happened, below is the best that I can come up with.
Its possible that in the case where changing to synthetic oil leaves an engine rattling could be due to the internal engine parts wearing and as they do the dino plating builds up and fills in between the worn parts. After a very long life of this happing the engine parts can become quite crowed, then when a change to synthetic oil is made the synthetic starts to break down or soften the dino plating and prepares it for the next oil change. It wasn't until my second oil change that the rattles started. In my case the fresh dose of synthetic oil washed the softened dino plating out from in between the engine parts. With the plating gone there was enough room for some of the engine parts to rattle.
Should I Change To Synthetic Oil
This can be a tuff question. There are good reasons for using synthetic oil but there are some reasons not to. You may be able to justify making the change then later on find something you or your motorcycle may not like about the new oil.
First, I don't recommend changing to synthetic oil in older high mileage engines. I think I pretty much covered this in the above chapter about leaks and rattles. Nobody knows how many miles is to many, nor does anybody know how long is to long. In my opinion, if an engine is well into it's life and doing well with crude oil, then just let the sleeping dog lie.
Many feel the need to switch to synthetic because of its better cooling properties and that's a good reason. But I'm more inclined to think this is more of a benefit to the much hotter air cooled V-twins rather than our liquid cooled V-twin Shadow engines. The better cooling really only helps to take the edge off of some of the 'extreme' heat that some engines are plagued with.
Some feel that the better cleaning is worth going after and synthetic oil is cleaner but is it that much cleaner than the newer crude oils to pay four or five times the price for it?
Others think that this new mystical wonder will add years to the life of their engine. So far I can't find anything to prove that synthetic oil will add on more mile to the life of an engine, only marketing claims.
One justifiable benefit to synthetic oil that I can come up with for using it in our Shadow's is it can go a few more miles between oil changes as compared to the crude base oils. The problem I find is that few people do this, and there is even fewer people that can. Few people will let there oil go past 3,000 to 4,000 miles no matter what type of oil they are using. Others like me may not ride more than 3,000 to 4,000 mile a year, that means you really need to change the oil out before winter and that means before its mileage life is up.
Others just buy it because they believe it's the best oil they can buy for their ride. Well that's fine. Its even better if they do that knowing what the oil is really doing for them.
Below is my personal view about the synthetic oil and my Shadow.
If the extra cooling is going to do much for me. If it don't lubricate any better. If I'm not going to extend my miles between oil changes. It does clean better, but the newer oils cleaning ability is getting better and if changed often these engines are getting 100,000 miles and are pretty clean when they get taken apart. So do I need synthetic oil at all ? Is it worth paying $5.00 to $8.00 a quart. Here is where marketing hype comes into play. Give it a good add, price it high, package it pretty and people will by it just because they think it’s the best oil they can get and they want the best. Do I want to take the chance of putting it in my used engine that has already had a life of dino oil in it? I'm asked quite often if some of the heavy duty truck oils can be used in our Shadow's. Yes they can, in fact from the research I've done and the testimonies I've heard about or read seem to lean towards these oils as a very good choice of a Non Motorcycle Specific oil .
Motorcycle companies for years have tried to convince us, the motorcycle owner, that we needed to or must buy their name brand oil, be it Yamalube, Honda, or Suzuki oils. They've tried to brain wash us into thinking that their oil has mystical or magic potions in them that is required to make our motorcycles work properly. Many dealers have even used fear as a tactic to get their customers to buy their line of oils.
The motorcycle companies claim that their oils have more needed,
Detergents, Higher levels of ZDDP, Special shear stable polymers, Special anti-foaming agents, And no friction modifiers like are used in the automotive oils.
But one should be aware that the above list of claims are just that, claims. The last time I checked some of the motorcycle brand oils only claim to meet API requirements of SF or SG but they didn't have the API certification seal on them, so they can claim a lot but are they what they claim?
The Heavy Duty Truck oils like, Mobil Delvac 15W-40, Shell Rotella-T 15W-40 not only meet the API requirements for Diesel engines but they also meet the same API requirements for gasoline engines that Honda recommends for our bikes, that being either of the SF, or SG ratings. This is the first point where the Heavy Duty truck oils differ from their automotive counter part. Another area that these two oils differ in is the truck oils are not, nor are they required to be an Energy Conserving oil were many of the modern automotive oils are, or the lighter weight oils anyway.
Here is something interesting about the truck oils as compared to the motorcycle specific oils. Diesel engine requirements for oil is,
Extended oil change intervals, Better engine cleaning, Long engine life, Special suspension agents to keep deposits from building within an engine, And special anti-foaming agents.
If you break the above list of diesel engine oil requirements down it would better equal the claims made by the motorcycle companies for their oils better than any other line of crude based oils.
Extended oil change interval = Special shear stable polymers. Better engine cleaning = More detergents Long Engine = A higher level of ZDDP Anti-foaming agents = Same as the motorcycle specific oils.
Oil is always changing, the EPA is always being pressed to clean up the emissions from combustion engines and as new laws are passed, new mandates put into place, then new API certifications will be made. But right now the additive packages used in the heavy duty truck oils mimic the claims for the motorcycle specific oils, and the truck oils are API certified.
Understanding The Manuals Oil Change Intervals.
The Honda owner manuals that come with our motorcycles have a section in it where it recommends service requirements or intervals. If you look at the part about oil changes you'll see that it recommends oil changes at 8,000 miles. To me that's pretty straight forward, so I thought. I read it and pretty much wrote it off. I mean, get real, 8,000 miles between oil changes, they have got to be kidding. There is no way that I would consider going that many miles with any type or brand of oil, synthetic or crude. But that's what Honda recommends. I thought it really odd to find that they are two different views of this issue.
One very common view is that Honda recommends a 8,000 mile oil change interval, then I should probably go 8,000 miles. Honda motor company knows best!
But let me give you another view of this. When the manufacturers write up owner manuals for our vehicles and list requirements for things like, oil changes, coolant changes, air filter replacements and so on they are not really telling us to run the vehicles that many miles before we change the oil or do some other service. What they are really saying is, that the listed mileage's are really dead lines, so if you exceed the specified mileage intervals you may void your warranty!. Let me say it this way, yes you can go the 8,000 miles that's listed in your Honda owners manual but doing so is pushing the limits of the oil to near the point of engine damage. I don't recommend running any oil that many miles in our Shadows and the many mechanically knowledgeable people that I've talked with don't think it's a good idea either. Don't think of the 8,000 miles as a good thing. Think of it as, your oil is getting to a point of being 100% depleted. I really don't know how much of the 10W-40 viscosity rating would be left after running it 8,000 miles in our bikes but I'm thinking not much above it's base number.
Below is a general guide line that I recommend for oil change intervals for our Shadow's,
Crude based automotive oils = 2,000 to 2,500 miles max. Crude based motorcycle specific oils =3,500 to 4,000 miles max. Heavy duty truck oils = 3,500 to 4,000 miles max. Full synthetic oils = 5,000 to 6,000 miles max.
MarkC
|
If You Found This Page Surfing The Web You Can Click Below To Go To My Main Web Page.