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Synthetic Oils

Discussion in 'Motorcycle Tech Talk' started by joejoe3, Jul 27, 2006.

  1. stevenh

    stevenh New Member

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    I just bought some Castrol Syntec 20/50... Is this okay to use? There was no mobil 1 at Wal mart.
  2. ridehard95

    ridehard95 New Member

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    each ther own

    synthetic will keep your motor clean thats a fact and it doesn't brake down like standered oil will . But if your bike has some miles on it and you change over to synthetic you will get leaks . Like I say in my post each to there own but I really think changing your oil every 1000 to 1200 is not a waste of money. The price difference between the two oils I can change mine often. And dirt is dirt . And I have heard about about bearing skip with synthetic when used in Harley Davidson do to the fact of needle bearings.I want it under stood that I don't know if synthetic is better or not. But I have been riding for 31 years and never had a problem with good old HD oil and changing your oil often is a good thing it gives you a chance to look the rest of the bike over
  3. gumby321

    gumby321 New Member

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    i JUST SPOKE TO MY H.D. DEALERS MECH.

    As some of you might know I have been going through some things with my 91 FXR P. I brought the heads,pistons and barrles to our machine shop here in town. I got great news from him. It is only the valve guides that will need to be done. Ofcourse he will be doing the whole top end. Honeing and the rest. I am hopeing to get it back this week some time.

    I also want to let it be known that I believe the reason for this was because the bike just wasen't taken care of. What I mean by that is SIMPLE OIL CHANGES. It doesent seem like that they were done too often. So when I went to do my third oil change in less then 300 miles of riding and the oil looked dirty that same night I knew something was up.
    I took out the oil tank and washed it flushed it and did it over and over again.
    Until I saw the bottom of the tank nice and clean with now slaag or any other garbage in the tank. Then I went to work on everything else that the oil went through.
    I changed all my oil lines and some other older lines from other spots just to renew and refresh everything that I could possably change.
    I figure if the oil wasen't changed nothing was taken care of correctly.
    So now we have a new start on life.
    I am also going with the synthetic oil. The Harley Oil, this must be done from the start of a rebuild. If you start with it you need to stay with it. That goes for any oil as far as I am concernd. What I used to flush the tank with was karosen. It's in the book so it must be right.
    I want to thank everyone who gave me all your suggestions. A special thank you to Dave without much of his wisdom I would have not had many of the ideas that he put on the table for me.
    Heres to some great riding weather for you all. It just so happens that here in Vegas it went from over 100 down into the low 80's. It's a nice time to ride here. T ake care everyone and thanks again. I am sure we will speak real soon. Gumby Peace
  4. CD

    CD Guest

    That and many other statements about synthetic oil are pure B.S. If you take some time and read the engineering studies and lab tests by professionals, you will find that there about as many wife's tales about it as there are UFO reports. It is unfortunate that there are so many uninformed HD grease monkeys that spread this nonsense from a purely uninformed position.

    Corvettes including the Z06 come with synthetic from the factory as did the Taurus SHO which had a bunch of needle bearing in that engine. Porsche's come with it as do other cars right from the factory. Air cooled, water cooled, it does not matter.

    Propagating myths like these old wife's tales by supposedly "expert" service managers only serves to continue the trail of B.S.

    if synthetic oil is bad for needle bearings, why does HD sell it? Oh, maybe it has magical properties that prevent skate?

    I would love to see a petrochem engineer have an open discussion with one of these HD experts. But, if he is wise he wouldn't bother because he would be debating with an unarmed person.


    I would be interested to see some lab results from a 1,000, 2,000, 3,000 mile oil change to compare the condition of the oil and the amount of debris in the oil filter. Unlike our oils used up to the mid '60's or so, vast improvements in detergents, additives and suspension agents have made oil live a lot longer under most conditions.

    Like you, I have been wrenching and riding for more than 40 years and agree that keeping fluids clean is paramount to longevity. IMHO, changing oil every 1k is overkill for me since I run Redline and know it can hold up under very demanding conditions.

    One thing to note is that most engines are broken in with dino oil before switching to synthetic. Why? Because synthetic oil lubricates the cylinder walls so well it can prevent fast ring seating. Doesn't have a thing to do with it being too "slippery" it has to do with it's ability to lubricate and cling to surfaces.
  5. ridehard95

    ridehard95 New Member

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    Each to there own

    Like I said in my post I don't know one way from the other if synthetic oil is better or not .I don't take much faith in what engineer's say My Dad told me long ago don't ever trust a fat lawyer or a skinny cook. And I think engineer was in there some where LOL . I know a couple real good HD mechanics and they have been building engines for years on the track and off .And they swear by Harley oils, I Don't think that makes them HD Grease monkeys as you reply. Rather the stories are true about synthetic or not there will always be a few that disagree. Thats what makes this such a great country . And as far as why does Harley Davidson sell synthetic oil I really don't know . I am still trying to understand why they built the V-Rod Like I say each to there own Ridehard95 Titusville Florida
  6. ironhorse

    ironhorse Active Member

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    I have really enjoyed the Great oil debate and I belive all are seated with firm opinions and own set of facts but the oil, either it be Redline, amsoil, castroil, hd oil valvoline, or walmart bottom shelf imported from china brand, there is one major factor that maybe I passed over but your oil is only as good as your filtration. You can run your high dollar best in the world oil with a cheap filter and it will resault in the same destructive capability, your filter is the reason your oil stays clean during its service life. I run synthetic oils front to back in all my vehicals, and I change the oil filters twice per oil change, my own cheap investment in piece of mind.
  7. ridehard95

    ridehard95 New Member

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    true

    You are right about a good filter and changing your oil often. I am a frim beleaver that oil should be changed about 1000 to 1500 miles thats just me. I have gone to biker events where the traffic was heavy and the weather was hot and when I got back home I changed my oil after only putting 400 to 500 miles on again thats just me and I always change my filter every time I change my oil
  8. hotroadking

    hotroadking Super Moderator Staff Member

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    RH

    HD oil used to be manuf by Sunoco, there are only so many refineries in the US and the oils are blended by these same companies and rebadged, only the ingredients change from bottle to bottle.

    I used to have a link to a study done by some BMW riders (believe it or not they are probablyl the most anal motorcyclists when it comes to oil and maintanence, probably because they can't bolt on chrome LOL)

    Anyway Don't fret over syn to dyno hd, however, next time you change, take a moment and run HD syn 20w=50, especially here in FL. You'll see a difference in noise and temps on the motor, and I know how hot it gets on these air cooled in the summer.

    Just switched a buddy on his 01 Ultra over to syn, he'd been under the same thought process as you, now his trans snicks vs clunks the motors making less noise and the temps are down. (Digital stick so we know)

    Either way change it often and ride it often.

    CD's comment on wrenches and shop owners should focus on the uninitiated and those not willing to learn from the experiences of others.

    As far as engineers to end users , yep sometimes you wonder what an engineer was thinking when they put something in a strange place, like the ac unit next to the number 8 plug on a mid 80's vette you can't get to it.

    Then again they thing of assembly and packaging more than working on the things.

    In any event Syn will help you out, but its not necessary.
  9. gumby321

    gumby321 New Member

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    Hey CD, about your last paragraph in your post about the synthetic being to slippery. I must say that I have already changed the filter and when I change my oil I put oil in the filter. Plus I also put in 2/3 of a qt in my bottom end , after cleaning it out of all the old oil. So my question now is do you think I should take the syn. out of the bike and put a new filter on and start with differant oil? Can I just add some LUCAS to it to make it a bit thicker? Whats your take? Gumby Peace
  10. gumby321

    gumby321 New Member

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    Since Day 1

    I have the same problem as we speak.I have been in the proccess of rebuilding the top end of my FXR. I have been riding since the late 60's and this question has been going on since I can remember. I just wish there was a difinitive answer to this question. You will never get one though. It's just like whats better to wear? boxers or breifs? Everyone has there one thought on this. From now to back to the 60's there have been leaps and bounds in the quality of oils. Plus there are many more now on the market. So we all want the best. When you find out please let me know what to use. gumby
  11. gumby321

    gumby321 New Member

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    Has Anyone Come Up With Any Good Suggestions

    Has anyone got any good and real oil facts?
  12. AZroaddust

    AZroaddust New Member

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    I have been working with lubricating fluids, both synthetic and fosil based for numerous years. I am not a tribologist so cannot give you a bunch of the technical mumb-jumbo, so I speak only from experience.

    I have seen everything from a 95/5 fluid (95% water - 5% glycol) used in underfground mining. petroleum and synthetics used in reciprocating and screw compressors, and you name it used in engines.

    Just like "experts" in a law trial I gaurantee you will find someone to say that X is best no matter what, while another will contradicat that and say that Y is best. There are pros and cons to both.

    However, one of the main selling features of synthetics and their high price is that you can go 2-3 times (or more depending on the application) longer before chaning fluids. If you are going to change fluids on a regular basis (every X hours or miles) regardless of what typr fluid you use, I would question the advantage of synthetics because of price.

    I'll probably get flack from both sides on this, but the point I'm trying to make is that I think it is a personal decision and no matter what you do someone will tell you "Don't".

    In my particular case, I have 16K on a 1995 883. After I exceed 24K it's being converted to a 1200, so I'm not too conccrned about what fluid I use right nowa and I have nor idea what I'll use after the conversion.
  13. gumby321

    gumby321 New Member

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    Thanks

    This Has Been Going On Since I Can Remember. I Am An Advid Oil Changer And Believe If You Take Care Of Her She Will Take Car Of You. The Syn. Oil Say You Can Go Longer Between Changes. I Will Probably Do My First 500 With The Top End And Change Oil And Then See What The Oil Looks Like At About 2000 Miles Or So. Thanks Gumby Peace
  14. CD

    CD Guest

    I hate oil threads because they tend to become more personal opinion than fact. Someone recently said they do not trust engineers. Well, get out of your chair, turn off your PC, don't walk on the floor, don't use the door etc, etc, etc. Engineers are the people that design everything you use in everyday life. How many engineering disciplines are involved in designing an HD? Since you ride it all you can, you must have some faith in their skills right? What is the difference between trusting an engineer that designs the oiling system and a petrochem engineer that develops the oil it uses?

    There are a few other things that baffle me
    1. Why doubt the voracity of tests done by independent sources? American Iron, Hot Bike and others have either directly or indirectly tested oils.
    2. Does a mechanic with a couple of decades of experience know more about the engineering aspects and performance of a given oil than a petrochem engineer or a professional in the field?
    3. Why do the urban legends persist? Too slippery for needle bearings? Have any one of you actually looked at a bearing that failed due to synthetic oil being too slippery? I know I haven't.
    4. Synthetics are too thin at temperature. Huh? How? The API rating for 20W50 means 20 weight (viscosity) oil Winter grade that performs as 50 weight (viscosity) oil at higher temperatures. If an oil whether dinosaur, synthetic Esther or paraffin based does not maintain the standard for a 20W50 oil through out the operating range or it cannot be classified as such. What would motivate an oil manufacturer to release a non-complying oil? That would be a sure fire method for getting kicked out of the API.
    5. Synthetics do not last longer than dinosaur oil. This one is pure malarkey. For one, synthetics run cooler than dinosaur oil so even if they had the exact same additives, there would be less tendency for the additives to oxidize. Synthetics have a much higher resistance to sheer so the oil is actually more capable of reducing friction and that reduces heat.
    6. Synthetics do not lubricate better than dinosaur oil. Wrong and blatantly false. The size of the synthesized molecules can be controlled while dinosaur molecules can only be controlled to a certain level. If you have the same sized molecules, friction is reduced and lubrication is improved.
    If someone can document a scientific example of dinosaur oil being superior to synthetics I would like to read it.

    Here is some interesting reading about the subject.

    http://en.wikipedia.org/wiki/Synthetic_oil

    http://reformed-theology.org/html/books/wall_street/chapter_04.htm
  15. ridehard95

    ridehard95 New Member

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    You can trust who ever ya want . As far as engineers go not all of them are dummier then a rock just a few of them.I have seen some real stupid ideas and claims by engineer's then I dare to think of . This is a world of pay and play this country is flooded by new products every day paint that claims never to dull or chip. Wax that claims to protect your paint from fire rain and ice. Fuel additive that claims to boost you to the moon.I use what I use because it works for me. I have never seen the need to use syntectic .I will always change my oil every 1,200 to 1,500 miles like I have for 31 years and that will never change. And know I don't not or will not believe every thing I read or hear about. But that is just me. If I ever have a problem with the type of oil I use I will look into changing to syntectic. And you can bet I will research both sides of the fence before I go dumping oil in my Harley just because you or some engineer tells me that its the best oil on the market. Thats what they said about the New coke-A- cola to. Engineers have done great things to make every day life a breeze and they also make it a big pain in the a@s too . And if people think that every product in this country is on the up and up because they don't want to get in trouble then I got some ocean front property for sell in Vermont. Consumers of been flooded with false claims for years and years .All I say is if it works for you use it and if you don't trust it stay away from it .And at this time and point I don't trust it but thats just me . If its slippery when wet and your happy thats all what counts
  16. hotroadking

    hotroadking Super Moderator Staff Member

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    This stuffs been beat to death, and I understand someone that hasn't made the switch and thinking about it' having some questions.

    All 20W-50 Syn and Dyno are the same viscosity (Slipperyness)
    so one is just as slippery as the other, the difference is Syn holds it's original properties longer and for higher temps meaning it's just near as good at 5K as it was at 500 miles. So it seems slipperyer.

    Dyno won't do that, it breaks down faster and it's protection is reduced over use at a greater rate than synthetic.

    Cleaning is better with syns for the same reason, less breakdown cleaner oil better cleaning of the engine.

    Leaks, - Better cleaning means the sludge that dyno won't remove might come out under syn and you get that base leak, not from the oil itself but becuase it exposed a weakness that good old 60 weight just blocked.

    Bearing Skate, I actually posed this to the engineers at Torrington, wish I had the response however the jest was that bearing issues are generally realated to two reasons:

    1) Incorrect bearing for the task
    2) Incorrect installation

    In that the bearing design is probably correct for the type of load, then when you hear a wrench say the synthetic wrecked the bearing vs taking the blame for a botched install well you can guess the reason why. Bad bearing to begin with or bad install. That simple.

    It's really amazing to me that someone would think that better lubrication would cause a part that is supposed to be lubricated to fail.

    Myth's aside run what you want as long as you change it and the filter regular.

    I will guess that if you live in a warm climate you'll see significant reductions in temp especially with the larger 96 HD motors by going syn.
    Last edited by a moderator: Mar 20, 2007
  17. gumby321

    gumby321 New Member

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    Hi CD, Well I took your info you sent me on sept,29 th about you recommending me not to use synthetic oil for my brake in of my top end.
    Not only did you tell me that but the guy who is doing my top end said it.
    Then there is everybody else who chimed in on the age old question.
    So now the syn. is out and I got the HD oil since I returned the syn. to them.

    I also have been intouch with SAM on the "OIL FIX" he gave me the price and told me that you have it there. This is a very small price to pay for insurance that you will not have oil leaks.(hopefully)
    Last night I also sent some questions on the HYLOMER,HONDA BOND and PIPE SEALANT after recieving your e mail on it. Simple questions, I am sure for anyone there with know how. Like, do I use the HYLOMER on both sides of the gaskets? Is this a special type of pipe sealant that is used on the threads so oil won't weep out of the cases or can I just go to a plumber and get some pipe sealant? In the artical you say you put the HONDA BOND to the TOP of the base gasket. If puting to the TOP why not both sides to prevent leaks?
    Ever since I have been asking I have gotten more then my share of input. Since you have told me not to use the synthetic and told me about the Oil Fix
    You are now the man...since you gave me all of these answers and I feel that you know, W.T.F is going on with FXR's and other bikes. You are now being picked as my sponsor for this job. In hopes you take this responsabilty.

    You talked about the nose cone and changing it to a steel S&S. I have looked up nose cone in my book and I have no idea what it is.
    Also the price of anS&S steel cone, how much could that be? Ball Park figure.
    Do you carry them? I will go to my chopper shop here and find out what the nose cone is. We have a very good relationship with each other. We are all frinds of Bill W. If you know who Bill W is you will understand. So he knows this is my first attempt at doing this, so he is trying to help me as much as he can. I don't want to stop him from his work. So I try not to bother him that much. He is a one man operation, but gets help every now and then from his brother.
    Thanks For All Your Help, Dennis G...aka Gumby321
  18. Tomflhrci98

    Tomflhrci98 Active Member

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    Ok. I am more than happy (and man enough) to own up to haveing said this somewhere on this forum. So I did my research and now I’m dangerous.

    "Oils with the suffix W are based on viscosities measured at -18 C" ... "Other viscosity numbers are based on measurements at 99C". These numbers such as 20W-50 are time based units call Sybolt Seconds or SSU or SUS. Therefore it takes more time for the same quantity of fluid to flow through the same orifice at 99C than at -18C. Thus, for lack of a better term it is supposedly thicker at 99C and thinner at -18C for 20W-50 rated oil.

    Umm oh-yeah, this is what you said.

    I smell a big butt coming……

    BUT, the thing I have a hard time with is that it goes against conventional thinking. All my life “hotter is thinner” (just like women).

    And I always thought that the reason oil pressure goes down as the engine warms up is because of this.

    So I guess, even though the oil SSU is higher at higher temperatures, the mating service tolerances within the engine grow as the engine gets warmer. This would allow the oil to flow easier and then pressure to go down. Right??
  19. CD

    CD Guest

    Exactly. Regardless of what oil you run, as heat increases so do tolerances. For example, when you build a SB MOPAR for Drag racing you set the tolerances for things like rod and mains at the outside edge or even a little more. Why? Because resistance to motion is decreased, friction is reduced and that means extra ponies. In reality you aren't real worried about it blowing up. It's all about HP and Torque and anything you can do to reduce friction helps.

    When dead cold, a high volume, high pressure pump can idle at 80 PSI. After you warm it up to about 180° your idle pressure drops to about 60 PSI and after the run it will drop to about 40 PSI. That is against a relief valve shimmed to relieve at 90 PSI or so. Back then, we were using Havoline racing oil and were changing it once or twice during the weekend. We had to use single stage filters because the volume could blow a two stage apart.

    We did experiment with turbine oil on a worn engine but, that didn't work very well at all. It was just a wee bit to thin and well, parts came out the bottom end on the first pass. :( :eek: Luckily there was no major damage to the crank or block. The track operators weren't overly happy with us that day though. Seems the oil didn't like speedy dry that much...:eek:
  20. CD

    CD Guest

    Gumby, the nose cone is slang for the cam cover. Since you are doing all that work, I would pull the nose cone and replace the stock plastic crap breather with an S&S steel unit. You can get them with a shim kit so setting it up is easy. To answer your questions regarding the Hylomar, it is called Honda Bond and it is what is used for a lot of gaskets on Acuras. There is an omission on the base gasket portion of the Oil Fix article. We coated the deck of the cases then laid the base gasket on it and coated the top. You use a very thin coat as it doesn't take a lot to do the job.

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