| Author | Message | ||
     Bullitt |
Don't know about use in my scoot anywhere but it's keeping my ancient air tools alive. Smells/looks a lot like ATF. Flushes out the dirt and water pretty well. | ||
| Majicmak |
Blake, If you have a Buell service book take a look at the Knife and Fork con rod set. Most modern bearings use inner and outer races of bearing steel. Not this one. The rollers ride on the conecting rod itself. Cast iron I think. The pin is hardened steel. Rollers are sized to fit with a very small clearance. How oil WORKS WITH the metal depends a great deal on how the parts are finished. Oil will tend to cling to a surface that is somewhat rough. Like one that is produced by a hone. A lapped surface is smooth as glass, and abrasive. Oil, REALY GOOD OIL, may not cling to it as well as the old goop to provide a cushion. Again- not a chemist. Is there a property of syn. oil that makes it sticky? Go back to the tire. Drive your car with bald tires out onto some smooth ice. Now floor it. You are not moving. No traction, no grip. To roll properly the bearings must get a grip. That old oil may be just what this bearing needs to work. The metal and the oil work together. I have never heard of a main bearing failure on one of these engines. They wear out I'm sure, but they don't seem to be an issue. It is this old, antiquated Knife and Fork con rod and the way Harley makes it. If these parts are lapped in as I have suggested, it makes them all the more unusual. Good cause for caution. Mak | ||
| Reepicheep |
I'm sure Blake will come back with the heavy math, I am clinging to a simple truth. How can a bearing have enough friction to wear a flat spot, but not enough friction to turn? If the oil is "so slippery" that the bearing can't even turn, then how can it have enough friction to wear a flat spot? For the car and tire analogy, I think blakes point has been that normal and synthetic oils are the same in terms of slipperyness, but that a synthetic oil won't break down so much from heat. For the first 1500 miles or so, the two are indistinguishable to your engine. So your car analogy would be to spin the tires on 2 inches of water, then spin the tires on 3 inches of water. Both hydroplane and float freely until you run out of water, and the result in either case is a siezed engine. It just takes longer in the latter case to run out of water. (if that makes any sense at all)... | ||
| Blake |
Mak: Most precision roller bearing races are manufactured by lapping or an equivalent abrasive technique. Connecting rod bearing races are cast iron? I highly doubt it. Think carbon steel. Very hard carbon steel. "A lapped surface is smooth as glass, and abrasive. Oil, REALY GOOD OIL, may not cling to it as well as the old goop to provide a cushion." I'm not sure I agree with your contention that a lapped surface is inherently abrasive. "Smooth as glass and abrasive"... which is it? Can't have both can you? And, again, the ONLY property of a motor oil germane to roller bearing operation is, listen closely, viscosity. "Go back to the tire. Drive your car with bald tires out onto some smooth ice. Now floor it. You are not moving. No traction, no grip." That is a totally invalid analogy. The con rod bearing's rollers do not have a huge mass (an entire automobile) impeding their motion; neither is a roller's rotation a result of torque being applied through an axle. A roller's motion results from opposing tangential forces imparted by the oil films on the outer and inner races. Take the tire off the car, roll it accross the ice, or put the car in neutral and push it accross the ice. Those are much more applicable analogies to the physics of a roller bearing. "To roll properly the bearings must get a grip." Are you implying that the roller must physically touch the races? That is not true. At operational speeds, the rollers do not touch the races. A thin film of oil separates them. The rollers turn due to forces acting on them by the lubricating oil which is in turn acted on by the bearing races. Like you said earlier, remember?... The oil actually impedes the bearing from spinning freely due to friction within the oil (viscosity). You've got to let go of the notion that some oil is more slippery than another. For thin film lubrication scenarios, slipperiness simply depends on viscosity. That is it, nothing else. The knife and fork con rod configurations may be old, but they obey the same laws of physics as other designs equally as old, as do the bearings they employ. There's no majic or hidden technology in HD oil. It is good motor oil, nothing more. | ||
| Buelliedan |
For once Blake and I are agreeing on lubrication issues!! He is absolutely correct. Viscosity is the only thing that matters in roller bearings. Synthetics have superior abilities to hold their viscosity which makes them a better product for our bikes especially where heat is concerned. I think too many people think synthetics are some "vodoo" products made in Dexters laboratory. They are not. All synthetic oil is is picking out oil molecules of the same size. This makes it easier to know the properties the oil will have and use additives specifically for that size molecule. Thus resulting in oil that breaks down slower and provides consistent viscosity(there's that word again) and resistance to thermal breakdown. Dan http://www.lube-direct.com/ddunn | ||
| Robr |
Check out this: oilscare And this: oilfacts | ||
| Robr |
<snip> | ||
| Majicmak |
Blake, I ran this up at the shop this morning:"I have this bearing and I want to lap it in" They looked at me as if I had three heads. Gave me all the reasons against as I have put forward here. One tool maker remarked " It's the wrong way to finish it. The roller will not grip." I knew what they would say ahead of time. But we are going around in circles here. I do not understand chemestry and you can't make a bearing. So lets look at something less abstract. Model Aircraft Engines. There are two types of construction. Ring and ABC. Ring, meaning it has an aluminum cylinder, a cast iron piston and a piston ring. ABC, Aluminum Piston, Brass Cylinder, Chrome Plated. The Hobby shop sells two blends of fuel by the jug. One with synthetic oil (Blue marker dye) the other with Castor oil. (Red) The Ring uses synthetic. The higher perfomance ABC uses Castor. Here it is the synthetic oil that is the lower grade. The ABC Motor has no piston ring. The fit at the top of the cylinder is ZERO clearance. It needs the Castor to work. Life on one of these is about 100 hrs. You replace the piston and sleeve and scour all the castor varnish out of the rest of the motor. Realy Blake, and there is no controversy on this subject. It is S.O.P. to use Castor,and synthetic oil is not used in the ABC motor. Got to the Hobby shop Saturday and find out for your self. Harley is going to mess with your head man. They are going to re-package Mobil 1 as V Rod oil and charge $10 a quart for it. It will Rage! Mak | ||
| Buelliedan |
Mak, Are you sure that that airplane engine has ZERO clearance in the cylinder? Wouldn't that mean there is absolutely no room for oil to get between the piston and the cylinder wall? Remember a loose engine runs faster than a tight engine but durability is affected proportionately. Castor oil used to be used in aircraft engines also. These would run the oil thorough one time and just dump it into the air. Required a lot of oil but you also didn't need to worry about any viscosity breakdown. I have a feeling this is what the model airplane guys are doing as well. But to end this argument just ask yourself what the purpose of oil is inside your Buell? Your argument says it is to provide friction for the roller bearings to work? Does that make sense? Or is the oils job to help prevent friction? That makes much more sense to me. Think about that | ||
| Sarodude |
Mak- 2 or 4 stroke RC engines? Also, just to clarify for those not familiar with the RC world, ABC is Aluminum piston in a Chrome plated Brass cylinder. Mak's wording left it a bit vague as to where the chrome cameinto the picture... -Saro | ||
| Blake |
I remember running my little Cox hand-line P51. That was a total blast as a young boy interested in aeronautics/aerospace. It used castor oil in the fuel. Mak: I don't EVEN want to try to exlain to you why one model airplane engine uses synth and anther uses castor oil. I can assure you that it has NOTHING to do with the lubricants' abilities to lubricate. More likely it is related to the combustion process. One may have higher compression, higher temperatures thus needing the different oil. You are talking about two cycle oils here; they must also perform well as fuel additives. Let's not cloud our discussion with that. Please?  I dunno what to say about your associates' comments on lapping a bearing race. The Buell service manual itself gives instructions on lapping the con rod and main crank bearing races. How DO they think bearing races are manufactured? Like I said, "lapping or an equivalent abrasive technique." Some interesting tribological terms... Elastohydrodynamic lubrication: In rolling element bearings, the elastic deformation of the bearing (flattening) as it rolls, under load, in the bearing race. This momentary flattening improves the hydrodynamic lubrication properties by converting point or line contact to surface-to-surface contact. Hydrodynamic lubrication: A system of lubrication in which the shape and relative motion of the sliding or rolling surfaces cause the formation of a fluid film having sufficient pressure to separate the surfaces. Lubricity: Ability of an oil or grease to lubricate; also called film strength. Question: What's slipperier, KY Jelly, or HD 20W50? Who cares, either way, someone is going to get screwed.  Blake {theKYisslipperier) | ||
| Blake |
Robr: One of the oil facts you linked to is dead wrong. Anyone know which one it is? | ||
| Leveg |
Blake says: "Synthetic oil is NO more slippery than any conventional oil with the same viscosity. The viscosity is what determines how slippery an oil is, that's it. Really!" Every manufacturer of synthetic oils that I could find on the net recommends that new engines are broken in on mineral oil before using their product.. This includes Redline, Mobil, Neosynthetic, Amsoil, Bel-Ray, Castrol, and Royal Purple. Why? They claim that their synthetic oils are too slippery to allow the rings to bed properly, possibly causing glazing of the cylinder walls. Redline oils have a graph on their website showing that their 15w/50 viscosity oil has a lower co-efficient of friction (slipperiness) than a competitive oil with the same viscosity. Viscosity is what determines slipperiness only under hydrodynamic lubrication conditions. There are 3 other regimes of lubrication that occur in engines, all of which are affected by oil slipperiness (co-efficient of friction), and so I make the claim again that a synthetic oil can be more slippery (lower co-efficient of friction) than a mineral oil at the same viscosity. If we want to be pedantic, we could qualify this with "except under hydrodynamic conditions. | ||
| Buelliedan |
Leveg, I bet if you checked those mineral oils at operating temps compared to synthetic oils at operating temps you would find a huge difference in viscosity even though they are the same weight oils. All things need to work together. Don't take any one figure by itself. By the way, New Corvettes come from the factory filled with Mobil 1. You can use synthetics for break in provided the engine is built properly. Dan | ||
| Robr |
Blake, is this it? Synthetics should be used during break in False:They are too slippery to allow parts to rub together and "break in" with each other. Less slippery fossil oils allow the parts to break through the oil film for metal to metal contact to wear in together. Fossil oils should be used until the engine is broken in. After break in you may switch to synthetic which will slow down further wear since the last thing we want now is metal to metal contact... ...less slippery fossil oils...this sounds kind of fishy to me and similiar to what we have been debating. A fossil oil should not allow metal to metal contact unless it has broken down already. So why do engine manufacturers not recommend synthetic oil for break in if its anti-wear properties are akin to fossil oils? Rob. | ||
| Leveg |
Buellidan Yes, some new cars come with synthetic oils from new because the factory uses a ring/finish package that allows their use. The point I'm trying to make is that the synthetic oil manufacturers acknowledge that their product produces an effect different from that produced by mineral oils, because of their superior slipperiness, and unrelated to viscosity. The mineral oils allow a controlled rate of metal to metal contact to produce engine break in, as stated by Robr. By the way, I don't believe for a minute that this slipperiness causes roller bearings to skid and wear. | ||
| Aaron |
Leveg: Where did you get your information about Mobil supposedly not recommending synthetic oil for break-in? Or that it's slipperier for a given viscosity than dinosaur juice? I got a totally different story when I called them (1-800-ASK-MOBIL). They told me that the notion that engines won't break-in properly with synthetic is hogwash. They say the only reason not to use synthetic during break-in is cost, because it's advisable to change it soon and therefore the extra cost of synthetic may not be justified. Look here for supporting information from their web site. I'm not an expert on any of this by any means, but I tend to believe the engineers from a major oil company. I'm curious about where you got a different story from them. BTW, the company position is also that the flat-spotting roller bearings story is hogwash. Chuck Kalbach, a Mobil engineer, wrote about this in American Iron awhile back when they had the great oil debate. AW | ||
| Aaron |
Ohh ... even better ... Click here, then follow the link "Why Synthetic ... Myths About Synthetics" ... here's what it says: "MYTH: You should break in your engine with conventional oil, then switch to Mobil 1. REALITY: The tighter tolerances and improved machining of today's engines have reduced the significance of the traditional engine break-in. Few manufacturers call for any special consideration. Since Mobil 1 is factory fill in Corvette, Viper, Porsche and other high-performance vehicles, engine break-in is obviously not an issue with current-generation vehicles. If your engine is an older model that has been rebuilt, you may wish to follow the original engine break-in schedule. In this case, where you may be changing the oil after just a few hundred miles, you might want to use a conventional oil initially and switch to Mobil 1 once you have reached a mileage that permits longer oil drain intervals." I'm fully aware that the word of a major oil company is not going to change everyone's mind, old myths are hard to kill. But it's good enough for me. Plus, my experience supports it. AW | ||
| Leveg |
Aaron Mobil 1® During Engine Break-In Many performance-engine builders recommend against using synthetic motor oil, such as Mobil 1, during the break-in period. Why would they make such a recommendation? -- Big O Dave, Newhall Due to tighter tolerances and improved machining of today's engines, the traditional concept of "engine break-in" is not as critical. However, if your engine builder recommends a break-in period with a conventional oil, we would suggest following their instructions. In this case, you should use a short drain interval on your initial oil fill. The reason for the break-in is to allow the valves and rings to "seat" properly. The concern is that the superior lubrication qualities of Mobil 1 Tri-Synthetic series motor oils may not allow for the proper break-in. Keep in mind that Mobil 1 is factory fill for the Chevrolet Corvette, Dodge Viper, all Porsches, Mercedes-Benz AMG and all Aston Martin cars. Most synthetic companies are recommending 6000 miles on mineral before switching. They all employ engineers, and they all want to sell as much oil as possible. I believe that companies like Redline use a higher class of synthetic base than Mobil 1 - polyol esters, as opposed to lower grade diesters. I also came across recommendations from companies like Toyota Racing Development and B.M.W. to not use synthetic during initial break-in. | ||
| Aaron |
The way I read it, their answer to "Big O Dave" basically says it's not necessary, but if your engine builder says use dino oil, use dino oil. Very diplomatically covering their posteriors. Yes, I'm aware that Red Line recommends conventional for break-in (3000 miles is what they say on the side of the bottle). Can you give me specifics about what other oil companies besides Red line are advising against synthetic for break-in? | ||
| Aaron |
LeveG said: "Every manufacturer of synthetic oils that I could find on the net recommends that new engines are broken in on mineral oil before using their product..This includes Redline, Mobil, Neosynthetic, Amsoil, Bel-Ray, Castrol, and Royal Purple." I've done some poking around trying to verify this claim. I've been able to support it with respect to Red Line and Castrol. Mobil clearly denies the information, as I've shown. I just got the following e-mail from Amsoil as well: Hi Aaron, There is an old myth that is still going around that the use of synthetics will not allow your engine to break-in. Not true. In fact , more and more vehicles are being filled with synthetics at the factory level. We do suggest that you go at least 500 miles on your factory oil before changing. The only reason for this is just to filter out any metallic particles associated with a new engine,but you can switch to AMSOIL at any time. Sincerely, Ed K Tech Services Like I said, I'm no expert on lubrication or engines. I do know a little about human nature though, and I know that sometimes stories just get repeated so often they become accepted as fact. Coupled with the fact that I haven't seen any real credible evidence to the contrary, and I've broken in over a dozen motors on synthetic without a single issue, I'm inclined to believe Mobil & Amsoil's version. So why would some companies promote the myth? I could see how it's in their self interest to lead people to believe that their oil is somehow slipperier at the same viscosity. But if you read their claims *carefully*, they don't actually say that. For example, Red Line claims the "lowest coefficient of friction available". That doesn't mean lower than anyone else's, but I think that's the interpretation they want people to make. Castrol says a lot about reducing wear, but they don't actually say it's from reduced friction versus other oils of the same viscosity, at least not that I can find. Reducing wear compared to what? And is it possible the reduced wear can come from other properties, like greater resistance to thermal breakdown? These kinds of statements seem designed to mislead, to me. Like slick Willie saying "there IS no sexual relationship". Always listen carefully. AW | ||
| S2no1 |
Geesh guys. Didn't we cover this a few months ago. Here's all you really need to know about oil. DINO OIL GOOD SYNTHETIC OIL BETTER NO OIL BAD, VERY BAD. Arvel  | ||
| Clydeglide |
Hey, when I asked about breaking in an engine on Mobil 1 Aaron's answer was 1-800-ASK-MOBIL. So I did. Mobil stated the ONLY reason to NOT use synthetic was economic. Why drop $30 worth of oil in 500-1000 miles when you could drop$5-6. I put Mobil 1 in my rebuilt '86 Jeep CJ from day one. 7k miles later its running fine and break-in was a non-issue. Had this same discussion with the techs at the local HD store including the bearing skidding. I said you could use synth from day one, they didn't agree. I told them when I get my next new bike I'm going to put in synthetic while they're doing the prep just to prove my point. Clyde Too Slippery My Ass | ||
| Rocketman |
Sadly Paul morgan died in a plane crash earlier this year. He was the other half of Ilmor Engineering, as in McLaren Mercedes, who run Mobil 1. Before his death I attended a speech he gave. Fascinating stuff too. At the end of the speech he took questions from the audience. I asked him about his findings towards Mobil 1. He claimed that using Mobil 1 they'd seen significantly less engine wear, much to their amazement too. This is significant if you understand at what level Ilmor build and run engines. Anyway, he really was that enthusiastic, claiming he used it in his Vincent and CX500 Honda, as well as ALL his cars and bikes ! He said it is the best oil in the world. Shame it's £35 for a 4 ltr tub. TVR ALSO USE MOBIL 1 from day 1 !!!! Rocket in England | ||
| Leveg |
Aaron Links as requested:- Neo Bel-Ray Castrol Royal Purple Amsoil T.R.D. Also this is a quote from Esso:- Low friction. The uniform structure of synthetic oil molecules means a lower friction coefficient compared to a similar grade of mineral oil. The lower the coefficient of friction, the lower the heat and energy input required to do the same work. Synthetics have been proven to lower operating temperatures and reduce energy consumption. Aaron, you said in one post "I tend to believe the engineers from a major oil company", then in a later post, suggested that they're all sh*tting us. | ||
| Aaron |
Uh, Leveg, you're not paying attention, I didn't suggest they're "all" sh*tting us, just some. Here's how I see it ... contrary to your claim, Mobil and Amsoil are in one camp, Neo/Bel-Ray/Castrol/Royal Purple/Red Line in the other. Now, which group is "sh*tting" us? Well, one of those companies is bigger than all the others combined, probably spends more on R&D than all those other companies do in sales, practically invented the stuff, certainly were the first to mass market it and have done a ton of development on it over the years. And they say the break-in story is hogwash. What's more, lots of new cars come with their oil as the factory fill, and I've personally broken in several motors with their product with no problems at all. So that's where I'll hang my hat. What's your rationale? AW | ||
| Blake |
Leveg: You might want to check the author of the Amsoil site; the link you posted is to some distributorship called bigskyoil.com. I've seen too many distributorship sites spouting all kinds of BS. Opinions and claims stated by distributorships are not necessarily representative of their suppliers. Likewise, the TRD (never heard of 'em) site is not a corporate site, rather a racing shop's site. Of course, even some of the suppliers practice shady marketing. The Royal Purple site actually claims that "Royal Purple will breath new life into older engines. The polishing characteristics of the oil will help smooth out the cylinder walls and bearing surfaces." That is THE most absurd, idiotic thing I have ever heard claimed about a motor oil. So on one hand, it's too slippery, and on the other it can polish metal??!! Polishing requires abrasion! The credibility of the rest of the Royal Purple site is thus nil. Pure marketing bullshit, that. The Bel-Ray site recommends to "Use when maximum power and minimum friction are required" and that its benefits include "Low coefficient of friction - Maximum power and superior fuel economy." Sounds great doesn't it? But, those statements apply to all reputable motor oils. None of those claims are specific to Bel-Ray or synthetic oil in general. See my point? Cultivating false inference in advertising is a powerful tactic. Learn to recognize it and you can sort the BS from the facts. "Redline oils have a graph on their website showing that their 15w/50 viscosity oil has a lower co-efficient of friction (slipperiness) than a competitive oil with the same viscosity." If you understand how Redline determined those friction coefficients, you will find that it was by a test that is designed to characterize the performance of EP lubricants. Those pressures are NOT present in the cylinder wall to piston ring scenario. Not even close. Is the data valid? It might be. Does it have any significance for a motor oil? No. For a tranny lubricant? Maybe. If synthetic is so damn slippery compared to conventional oils, how can it be used in a tranny with a wet clutch? It's important to be able to sort the misleading, insignificant marketing speal from authentic and applicable fact. A lot of shady marketing exists in the world of synthetic motor oils. The reduced friction line is one of the most prevalent. The results of EP wear scar tests are another. The only honest/applicable marketing I've seen for motor oil are the commercials by Mobil showing how a conventional oil at extreme temperature will cook to tar while at the same temperature, Mobil-1 maintains its normal appearance/characteristics; and also a similar comparison scenario at extreme low temperatures where the conventional oil had become very thick and slow to flow while the Mobil-1 maintained very good flowability. I guess the Castrol commercial is also semi-valid where a bunch of hard running V8 engines (one using Syntec, the others using various conventional oils) were drained of oil, with the Syntec engine being the only one to continue without seizing. Redline's claim that their chosen synthetic base is somehow superior is another example of bait and switch marketing speal. "Our product is new and different -->> it must be better." Not! Still believe synthetic oil is majic, that it's too darn slippery to allow proper break-in? Here's the proven equation for calculating the force (F) resisting motion between two surfaces separated by a liquid lubricating film. Where... "F" is the force of viscous flow resisting the motion of one surface relative to the other. "m" is the coefficient of viscosity of the fluid, "A" is the wetted contact surface area, "V" is the velocity of one plate relative to the other, and "n" is the distance between the plates (thickness of the gap, also the thickness of the fluid film). I'll let you draw the inevitable conclusions yourself. The bottom line is that you can believe the shady marketing speal, or you can believe the engineers/experts. Your choice. The facts, once understood and sorted from the BS, do speak for themselves. Shady marketeers love to come up with special names for their "superior" additives/formulations. Royal Purple has "synelec", NEO (sorry never even heard of them till now) touts "0" weight oils like they are some majical elixer heretofor unheard of in the world of lubricants. Whan a synthetic oil vendor claims that their product will "reduce friction and drag better than petroleum oils, resulting in significant fuel economy increases" (taken from Amsoil site) what they are saying is that the wider viscosity ranges afforded by synthetic oils improves cold running efficiency (lower viscosity when cold) and that the ability of synthetics to resist thermal breakdown keeps them from increasing in viscosity like conventional oils. Yes, you heard me correctly. Conventional oils due to thermal breakdown and oxidation can actually INCREASE in viscosity through their lifespan. As a result, fuel economy degrades. Let's ride! | ||
| Leveg |
O.K. guys, here's the scoop on Synthetics. I used to run a Drag Racing operation under major sponsorship from one of the big oil companies (in Australia). As such, I had the opportunity at times to discuss these issues with the people who design the oils. Tonight I rang the head of this companies technical department - this guy has written a paper on this very topic, and is considered a world authority. I offer this information to be informative, not arguementative. The point we have all missed, is that oil viscosity increases by an enormous amount under pressure. The example given was that a mineral based Auto Trans Fluid may have a Kinematic viscosity of 20 centistokes @ 40 degrees C. When a load of 80,000 psi is applied to this oil in operation, it's viscosity can increase to around 270,000 centistokes. (that's why an oil film is strong enough to deform metal bearings). By contrast, a synthetic version of the same oil under the same load may only increase it's viscosity to around 7,000 centistokes. So the 2 oils start of with the same viscosity as measured in the laboratory , but the synthetic oil has much less increase in viscosity under load. Under sliding contact conditions (plain bearings & rings) the synthetic oil has a thinner film (because of the lower viscosity) and therefore less temperature increase, both of which make it effectively much slipperier. Fact - synthetics are slipperier. However, under rolling contact conditions (Roller bearings), the roller bearing is continuously climbing the face of a small depression in the journal created by the contact surface deflecting under load. Under these conditions, the lower viscosity, thinner film synthetic may not lubricate as effectively as a mineral oil. A sythetic oil can be produced that has a higher increase in viscosity under load than a mineral oil, but it will then produce high friction, negating the other benefits. Fact - synthetic oils may cause abnormal wear/fatigue problems in high load roller bearing applications. Especially roller lifters and rockers in endurance race engines. I don't believe that this is a significant problem in Harley engines, and the technology is improving constantly. By the way Blake - T.R.D. = Toyota Racing Development. Factory race division - Highly respected ! Redline's claim that their oil is superior - Redline is made from Polyol Ester stock, which is approved for use in Jet turbines. The lower base synthetics are not. Conventional oils actually lose viscosity with use and time. Generally around 40% loss over 2-3,000 miles. Aaron, it may be possible to break an engine in on synthetic depending on the machining, parts, break-in procedure, etc. But, the chances of a bore glazing problem are likely increased when synthetic oil is used. The higher the grade of synthetic, the higher the likelyhood of problems. Maybe the one you're using is not that far removed from a mineral oil? | ||
| Aaron |
Well, since you brought it up, I'll add a little anectdotal fuel to the fire ... Cages: purchased 4 new ones since '92 ('92 F350, '95 Bronco, '97 Expedition, '02 Silverado). All came with dinosaur juice. All were converted to synthetic before they hit 500 miles, most by 200 miles (Delvac 1 in the trucks, Mobil 1 5W-30 in the others). No perceptible oil usage at any point in their lives, nor were there any other indicators of a ring seal problem on any of them. Bikes: purchased 5 new HD engined v-twins since '96. None went over 200 miles on their factory dinosaur juice before being switched to synthetic (usually Red Line 20W-50, chosen because it's the right viscosity and it carries CF-4, the mostest severeist heavy dutiest diesel rating, which Mobil does not carry except in Delvac 1 which is the wrong viscosity). No ring seal issues at all. More bikes: a handful of freshened top ends on various bikes over the last 4 years, for performance reasons. Unless the oil is old, I don't change the oil when doing a top end because I figure it's going to just get polluted with metal filings right away. So these freshened top ends got broke-in with synthetic before being changed out a couple hundred miles later, again with synthetic. No break-in issues whatsoever, oil consumption on all these bikes is negligible. Race cars: raced sports cars for 17 years, 11 of which were with a very maintenance intensive car. One rebuild every year in the off-season and generally at least one freshening during the season. Same oil change philosophy as the bikes, change it after break-in unless I have reason to believe the oil is bad. 18 Qt. dry sump system discouraged me from using synthetic until '91 when I discovered, quite by accident, that I had much more consistent oil pressure with synthetic. Switched from Valvoline 20W-50 conventional to Mobil 1 15W-50 at that point. Campaigned the car for another 4 seasons. In all these engine freshenings and rebuilds, I had one cylinder one time where I have reason to believe the rings didn't seat properly. That motor was broken in on dinosaur juice. Honest. So, bottom line ... if you want to worry about it, go ahead, but I won't. I've found what Mobil and Amsoil and Chevrolet and Porsche and others say to be true. Until I see otherwise, I'm too hard-headed to change my mind, as are you I'm sure  | ||
| Hans |
Leveg, you brought up a very interesting point about oils and viscosity under pressure: Specially important in relation with the roller bearings of our crankshafts. Hans. |
