Based on this information, I am sticking with Castrol Syntec or Mobil1 (whichever is available when I need it) in 20-50 in the enigine and I am switching to 75/80-90 gear oil in my tranny. No more engine oil in my sporties tranny again. This article makes quite a case that engine oil has additives to deal with combustion byproducts that your tranny simply does not need while at the same time testing has shown that wet clutches have better lock up when running in gear oil.

Check it out: http://www.sportster.org/tech/OilandtheHarleyDavidsonMotorcycle.pdf

Yes, this is an excellent paper by Lee.
Many of us on the XL-List sponsored the paper by
paying for the oil analysis.

Even before the paper I used Mobil1 15w-50 in the
engine and Sport-trans in the primary. Although I
have used Syn-3 in the primary once, I went back
to the Sport-trans since it costs less and performs
better in my bike.

Good read, thanks! My work is in fluid analysis, I run a lab at a university that does exactly this sort of thing, though mostly for hydraulic fluids. Some good info in there, though the real story would fill thousands of pages!! I like the author's attitude regarding the subject.

Moderator, can we make this thread a sticky or would that violate the authors rights in some way? Perhaps because we are simply linking to its origin its OK?

BTW, I have just purchased a quart of Mobil1 synthetic 75-90 gear oil and it smells just like Sportrans(very strong odor). I think its safe to say Sportrans is gear oil.

Yes, this is an excellent paper by Lee.
Many of us on the XL-List sponsored the paper by
paying for the oil analysis.

Even before the paper I used Mobil1 15w-50 in the
engine and Sport-trans in the primary. Although I
have used Syn-3 in the primary once, I went back
to the Sport-trans since it costs less and performs
better in my bike.

I did the exact same thing as you. I returned to sport-trans and I feel my tranny is performing better than with syn3. Also changed to Mobile1 15w-50 as well. Very happy.

Excellent Artical... Thanks for posting the link !!

So ... HD oil is good stuff after all (according to the article). That's what's in mine (Syn3). It's pricey, but only has to be changed every 5,000 miles.

Interesting stuff, once my head stopped spinning! Thanks for the link.

Wonderful paper. I second the notion that we make the original post with the link a sticky.

I disagree with the assumption that HD Syn3 is worth the extra money. They don't refine, process or in any way have a hand in the product (in spite of what you may hear). They merely have it packaged in their container, purchase it a jobber rates and mark the hell out of it... just lik everything else they sell.

The following is my own personal opinion and not to be construed as fact:
In the early days of oil refining we only had Pennslvnnia crude. At the time, it was considered to be the best available. Problem was it was paraffin based. That's the sludgy stuff we used to scrape off then heads from time to time. The going advice was to change oil every 2500 miles. Today's oil from the Mid East isn't paraffin based and have a much sweeter (low sulpher) quality. The oil companies were slow in revising their frequency and why not? They sell the stuff. We now see normal Dino oil advertised at 7500 mile frequency intervals. Can synthetic be hardier and les prone to breakdown?

I'm of the opinon that the only real culprits we havve to deal with today are induced water vapor and gas contamination. Without the two offenders, we might be able to literally never change oil, Indeed, when Mobil 1 was first introduced it was touted as just that. "Never change oil again", a statement the oil folks have since recapitulated on. At tis point I'm yet to be convinced that recapitulation isn't anything more than another marketing ploy. My point is this... I still doubt any recommendation given by the oil barons. That's like asking the beef council how often should I include beef in my diet.

Without imperical eveidence, I believe that oil change frequedncy may well depend on factors inclusive of the aforementioned culprits and possibly others. I will appreciate any input on the subject.

There is an exellent article on syn oils in november issue of american iron.

I disagree with the assumption that HD Syn3 is worth the extra money. They don't refine, process or in any way have a hand in the product (in spite of what you may hear). They merely have it packaged in their container, purchase it a jobber rates and mark the hell out of it... just lik everything else they sell.

The following is my own personal opinion and not to be construed as fact:
In the early days of oil refining we only had Pennslvnnia crude. At the time, it was considered to be the best available. Problem was it was paraffin based. That's the sludgy stuff we used to scrape off then heads from time to time. The going advice was to change oil every 2500 miles. Today's oil from the Mid East isn't paraffin based and have a much sweeter (low sulpher) quality. The oil companies were slow in revising their frequency and why not? They sell the stuff. We now see normal Dino oil advertised at 7500 mile frequency intervals. Can synthetic be hardier and les prone to breakdown?

I'm of the opinon that the only real culprits we havve to deal with today are induced water vapor and gas contamination. Without the two offenders, we might be able to literally never change oil, Indeed, when Mobil 1 was first introduced it was touted as just that. "Never change oil again", a statement the oil folks have since recapitulated on. At tis point I'm yet to be convinced that recapitulation isn't anything more than another marketing ploy. My point is this... I still doubt any recommendation given by the oil barons. That's like asking the beef council how often should I include beef in my diet.

Without imperical eveidence, I believe that oil change frequedncy may well depend on factors inclusive of the aforementioned culprits and possibly others. I will appreciate any input on the subject.

In the hydraulics industry, better technology in fluid analysis is making possible condition-based predictive maintanance scheduling. Hydraulic and engine oils are monitored on a schedule and changed when we notice either certain changes in the chemistry or the prescence of particle contamination.

Bottom line Will, you're right - there is NO truth in assigning a number to how long an oil will hold up. I've seen 2 identical machines running identical loads each using resevoirs full of the same hyrdraulic oils - one runs fo 50,000 hours and the other is taken off line after 5K to prevent catastrophic failure.

The 3,000 mile interval is certainly safe. But does that mean that at 3,500 your engine was going to be damaged? or at 5,000? what about 20,000? You have no idea, do you?

I'm surprised AMSOIL isn't in on there test.

I ran Mobil-1 75w-90 last oil change. It has a ver stong order that was noticable even when riding the bike. It also seem to weep is way out, though the drive shaft, I think, as after rding I would have very small droplets on my belt. I switched back to Bel Ray 85w gear saver.

Let me know how your experience goes witht he Mobil-1 75w-90.

Thanks for the great info!!! Since I live nowhere near an HD dealer...or anything else for that matter....it is comforting to know that my '97 is safe with Mobil 1 Syn. in her. Rick

I ran Mobil-1 75w-90 last oil change. It has a very stong odor that was noticable even when riding the bike. It also seemed to weep is way out, though the drive shaft, I think, as after rding I would have very small droplets on my belt. I switched back to Bel Ray 85w gear saver.

Let me know how your experience goes witht he Mobil-1 75w-90.I had exactly the same experience with Mobil 1 75w-90. And it seemed to shift very poorly, too. (When I drained it, it ran out like water . . . perhaps it's too thin for smooth shifting?)

At this point, I've had Syn3, Mobil 1 15w-50, Sportrans, Formula +, and Mobil 1 75w-90 in my '05's transmission. While my research has not been conducted in a controlled lab setting, my subjective experience is that HD Formula + is far and away the best fluid to put in a rubber-mount's transmission. Especially if you install it, run it a while, then change it again to get as close to 100% Formula + as possible.

For me, the matter's settled, the case is closed. I'll experiment no further--I'll run Formula + in my '05's tranny and Mobil 1 15w-50 in its engine. (I noticed an immediate reduction in oil temperature when I switched from Syn3 to Mobil 1.)

I've read this article before. My favorite part is still the section on how oil actually provides more protection later in its life than when it is brand new. Makes me wonder how many people on this forum believe they're babying their bikes by doing oil changes every 2000 mi (or some ridiculous number like that) when in reality they're wasting money and hurting the engine.

I was always under the impression that is was the filter that wore out/clogged long before the oil had exceeded its useful life. Hence BMW's have a special (and expensive) filter that allows them to go 15,000 mi between recommended oil changes.

Cheers,
Luke

I thought I would point out a few things about our bikes. First, with a 3.6 quart fill, we have a significantly higher oil-to-displacement ratio than most cars (my 5.4 expedition holds 6 quarts I believe, so that’s 1.11 ratio compared to our 3 ratio, even better if you have an 883). Also, our filters are bigger than many automotive filters (including the filter on the f-body ls1 motors) that serve engine 2-5 times larger than ours. So going by typical automotive change intervals is not really valid here. As someone pointed out, it’s not that the oil goes bad (although our engines are a bit of a torture test for oils, being air cooled), but that the filter gets clogged with contaminants. When a filter gets clogged it goes into bypass mode and you oil turns into liquid sandpaper (the cheep and easy way to hone your cylinders right :eek: ), but we all know this. So, if your truly worried about oil change intervals, save yourself 40 bucks in oil every 5k and just change the filter every 2.5k. But I argue, with the amount of oil we have and the size of our filters (especially if you get the longer HD filter, which I use and I believe them to be good high quality filters), that a 5k change interval is more than adequate. If you whish to have further protection for you bike, get a oil cooler with a thermostat, it will make you bike run cooler and your oil last longer.
Dan

Mobile I 20W-50 V-Twin Synthetic in the engine (Sporty and BigDog).
Mobile I 20W-50 V-Twin Synthetic primary (BD).
Redline Heavy Shockproof (BD tranny/Sporty primary)

Works good lasts long time!

That oil paper is pretty good. There's another one called the AMSOIL Motorcycle Oils Whitepaper. You can find it by following the 20W-50 link in my signature. You go to the 20W-50 product page and the whitepaper link is there along with another link for recommended oils for Harley applications PDF. The report results are notarized, and the tests included the following:

SAE Viscosity Grade (Initial Viscosity - SAE J300)
Viscosity Index (ASTM D-2270)
Viscosity Shear Stability (ASTM D-6278)
High Temperature / High Shear Viscosity (HT/HS ASTM D-5481)
Zinc Concentration (ppm, ICP)
Wear Protection (4-Ball, ASTM D-4172)
Gear Performance (FZG ASTM D-5182)
Oxidation Stability (TFOUT ASTM D-4742)
Volatility (Evaporation) (ASTM D-5800)
Acid Neutralization and Engine Cleanliness (TBN ASTM D-2896)
Foaming Tendency (ASTM D-892)
Rust Protection (Humidity Cabinet ASTM D-1748)
Wet-Clutch Compatibility (JASO T 904-98, limited review)

AMSOIL isn't always the best test performer, but it is always very good.

I agree with 1337-Sporty about the HD Formula +. I have used several tranny lubes and none works as well as te Formula +. Regarding Synthetic engine oil, I have used Amzoil, Syn3, Mobil 1, and Redline High Performance. I am staying with Redline. The Engine temp. is 10-20 degrees cooler, and my mileage went from 56 average to 61 on a bone stock 05 XL-883. I know Redline has a high moly content, but that's fine in a Harley where engine oil does not also lubricate the clutch.

I also agree with the Formula+ in the tranny/primary. Not scientific, but seems to shift smooter and quieter.

Also went back to the Formula+ in my BT primary, but Mobil 1 75W-90 Synthetic in the transmission.

ok, this article had my complete attention until i got to this statement.

engine wear actually decreases as the oil ages. what this means is that changing the oil frequently actually causes more wear than using more of the lifespan of the oil.


now that statement caused my ears to lay flat to my skull and start me looking a little pig eyed at the at the article. being a mechanic and an amsoil dealer i think that most oil is drained before its time. but the only to be sure is with an oil Analysis. given the quantity's we are dealing with it is cheaper just to dump it and start fresh. wait, wait, according to this dude maybe we should be paying a premium for and using used oil and our engines would last a lot longer. just think we could probably make money selling our used oil to some one whose oil wasn't as used as ours, therefor saving there engine for them. changing the filter is probably disastrous. the only wear caused by changing the oil to soon is to your wallet.

i read this post when it was new and debated until now whether to comment on it. but i think that statement is ludicrous.

Thanks for the article!

peeking out the curtain...dark outside...but...only see leaves on the ground...fall for sure...but no snow yet...not winter yet...too early for oil threads...we've just come out of the which-jets-for-me-season and should still be in the what-seat-is-best season...but definately not oil thread season yet...

;)
:tour

Do you know why the owners manual says to be sure to use oil that is approved for diesel engines?

Detergent agents are in diesel oils, help keep engine clean.

Do you know why the owners manual says to be sure to use oil that is approved for diesel engines?

Are you saying that non diesel oils do not contain detergents?

Some do & some don't, you need to look on the label for the detergent/diesel code CF, CF4, CG4, etc. The label will say something like SAE 20w50 API CG-4/SL. The CG-4 is stating that it is suitable for diesels. The SL is the quality/protection factor of the oil. Example; SA would be the lowest protection and SZ would be the best protection. P.S look for a rating of SL or SM

Are you saying that non diesel oils do not contain detergents?

So I must be the only person running Rev-tech Pure oil? It's not syn, but a hydro-cracked oil refined to be so pure, it ends up clear, and then they throw in a couple of additives. It's made for V-twin engines, and runs great in my 75 XLH......

Great info!
Just a side note on synthetic oil, I work on fighter jet engines for a living, these engines use a MIL-7808 synthetic oil and are subjected to extreme temperatures. The oil is never changed! Since there are no exhaust gasses leaking into the oil like there are on a piston engine the oil stays clean and there is no build-up of sludge and contaminants. The reason oil is changed so often on piston engines isn't because the lubrication properties break down, it is because the cleaning properties of the oil breakdown. Synthetic oil is amazing stuff!

Some do & some don't, you need to look on the label for the detergent/diesel code CF, CF4, CG4, etc. The label will say something like SAE 20w50 API CG-4/SL. The CG-4 is stating that it is suitable for diesels. The SL is the quality/protection factor of the oil. Example; SA would be the lowest protection and SZ would be the best protection. P.S look for a rating of SL or SM

Isn't it best to make sure that the oil used in a motorcycle also has an SG, SH or SJ rating as those oils have high zinc and phosphorus levels which protect the engine better than oils that do not have that rating? Isn't it also true that the plain SL and SM oils with none of the above ratings were reformulated to remove some of the zinc and phosphorus in order to keep them from damaging the catalytic converter in cars? If the oils have SG, SH or SJ ratings plus the SL or SM, they would be OK as well wouldn't they? The SL and SM ratings have nothing to do with increased motor protection as far as I know or am I all washed up in my belief that those ratings aren't necessary or even necessarily beneficial for the oil used in our machines? If my understanding is correct, there is no way that I would use a plain SL or SM automotive oil in my bike if it didn't have any of the earlier SG, SH or SJ ratings. Any comments from an expert would be welcome.

Anytime An Engine Oil Spec (api) Changes To A Higher Letter It Supercedes A Previous Letter
Ie: Sm Is Better Than Sj And Cj Is Better Than Ci And Is Backwards Compatible

The SL and SM ratings have nothing to do with increased motor protection as far as I know or am I all washed up in my belief that those ratings aren't necessary or even necessarily beneficial for the oil used in our machines?

Actually, SL/SM API specification require less wear tolerance, less tolerable foaming, etc. than SG/SJ oil.

Just better, all the way around than the SG/SJ API certifications.

If you have some time take a click over to bobistheoilguy.com. Users post real world oil analysis results for just about anything in the way of internal combustion engines. Greases, transmission fluids, etc. Lots of good reading. They even have virgin oil analysis so you can see the additive package in your particular brand of oil.

Yes, motorcycle-specific and diesel oils have slightly higher zinc/phosporus than automotive oils, but remember, the zinc/phosporus levels are less than ten percent of what they were 30 years ago. Oil chemistry has improved dramatically.... and you don't really need as much of this additive as in years past.

A favorite oil with the metric crowd is Rotella 15w40. It shows excellent oil analysis reports, especially considering that most metric bikes have a shared sump for the engine/transmission/primary. Two bad they don't offer it in a 20w50.

Automotive oil in a Harley crankcase is fine, as long as you're in the correct viscosity range.

Actually, SL/SM API specification require less wear tolerance, less tolerable foaming, etc. than SG/SJ oil.

Just better, all the way around than the SG/SJ API certifications.

If you have some time take a click over to bobistheoilguy.com. Users post real world oil analysis results for just about anything in the way of internal combustion engines. Greases, transmission fluids, etc. Lots of good reading. They even have virgin oil analysis so you can see the additive package in your particular brand of oil.

Yes, motorcycle-specific and diesel oils have slightly higher zinc/phosporus than automotive oils, but remember, the zinc/phosporus levels are less than ten percent of what they were 30 years ago. Oil chemistry has improved dramatically.... and you don't really need as much of this additive as in years past.

A favorite oil with the metric crowd is Rotella 15w40. It shows excellent oil analysis reports, especially considering that most metric bikes have a shared sump for the engine/transmission/primary. Two bad they don't offer it in a 20w50.

Automotive oil in a Harley crankcase is fine, as long as you're in the correct viscosity range.


I'd qualify your last statement by also following the specific Harley-Davidson Diesel Spec recommendations that are spelled out in the owner's manual. Not just any 15W-40 or 20W-50 automotive oil will meet those requirements. Most 15W-40 likely will as it is generally made for diesels and at least some 20W-50 will but the correct viscosity alone isn't enough.

I agree. I've read bobistheoilguy.com many times over the past few years and he makes some good points that seem generally right on.

I'm curious as to where you got your information from that states that oils meeting SL/SM oil specs require less foaming and less wear tolerance than SG/SJ oil. I'm not saying you're wrong as I'm no expert, rather I'm just curious about the information as I've read that the SL/SM oil was formulated without the zinc just to protect the catalytic converter and the newer designations had nothing to do with increased engine protection. If it did, one would think that motorcycle specific oils would have the newer designations as well. Last time I checked the motorcycle oils that I checked didn't. One manufacturer even explains that the higher zinc content of the older designation offers greater protection.

Don, I got my information on bobistheoilguy.com. I also went out to the web and read the API spec for SG/SJ oil and also for SM and SL.

SL/SM oils still have some amount of zinc/phosporus. Don't quote me, but I believe that the requirement is < 1200 ppm. Just as an example, the virgin oil analysis for, say, Mobil 1 5w30 - there's still 9xx ppm.

Also, the new formulations for SG/SJ are showing less zinc/phosporus. I'm thinking the target is no more that .6 -.8 %

You're right that most motorcycle-specific oils do not show SL/SM but I'm sitting here looking at the label on a bottle of Amsoil 20w50. Is says API service SL.

Ahhh - but less cam bearing wear for SM oil does not tell the whole story. High spring rates on push-rod engines show increased cam face wear with SM rated oil. This is where the increased levels of ZDDP are beneficial.

Don, I got my information on bobistheoilguy.com. I also went out to the web and read the API spec for SG/SJ oil and also for SM and SL.

SL/SM oils still have some amount of zinc/phosporus. Don't quote me, but I believe that the requirement is < 1200 ppm. Just as an example, the virgin oil analysis for, say, Mobil 1 5w30 - there's still 9xx ppm.

Also, the new formulations for SG/SJ are showing less zinc/phosporus. I'm thinking the target is no more that .6 -.8 %

You're right that most motorcycle-specific oils do not show SL/SM but I'm sitting here looking at the label on a bottle of Amsoil 20w50. Is says API service SL.

Ahhh - but less cam bearing wear for SM oil does not tell the whole story. High spring rates on push-rod engines show increased cam face wear with SM rated oil. This is where the increased levels of ZDDP are beneficial.


Thanks! I'll read further. That cam wear has been a concern of mine regarding the latest spec oils.

Anytime An Engine Oil Spec (api) Changes To A Higher Letter It Supercedes A Previous Letter
Ie: Sm Is Better Than Sj And Cj Is Better Than Ci And Is Backwards Compatible

If my information is correct, later specifications aren't always necessarily better, just newer. For instance, if my memory is correct the SJ oil has no different specification than the older SH oil spec. other than the manufacturer had to agree to off the retail shelf testing rather than providing a perfect sample to be tested. It just assured that the production oil would pass muster. I think it was similar with the SL oil. If my memory is correct (may not be right on which spec, SJ SH SL?) SL spec. oil wasn't supposed to be better for anything other than the catalytic converter due to it's lower zinc content. :)

When I had to decide what oil to use in my Ford Powerstroke Diesel I searched all over the internet for information and had oil analyses performed by the local Caterpillar dealership's lab.

When all was said and done, and based on the reccomendation of the oil analysis lab, I ended up sticking with the synthetic blend oil that Ford markets and recommends for that engine and changing it at the recommended 5000 mile frequency along with the filter they recommend. I could very likely stretch the oil change mileage on that truck to 7500+ miles by getting the oil analyzed often (some folks have stretched oil changes out to 20K miles and farther.)

For my Sportster, I'll probably switch to the H-D synthetic oil at the 1000 mile service in a couple weeks. (I changed the oil and filter at 500 miles like I always do on a new engine.) To avoid any crazy arguments should the worst happen, I'll use the H-D recommened oil filter.

Maybe that seems a bit sheep-like but, you know, if I have a problem I expect both Ford and H-D will stand behind me if I do what they are recommending.

The only time I ever seriously trashed an engine was when I decided that I new more about oil than the manufacturer did and used something I shouldn't have. I've tried to learn from that, rather expensive, experience.

just lookin around and tripped over this thread. there's some great stuff on here. there's one thing i did come across on another thread...somethin about oil expiring or going bad?? can that really happen? can oil sit too long in an engine? running or not? i never heard of that before. any enlightenment on this issue would be great.

My experience using Synthetic oil in motorcycles started in the 70s, long before anyone recommended it. As a matter of fact in those days almost everyone said it would make my bearings go flat and cause my motor to leak like a sieve. In those days a friend of mine owned a auto repair shop and also happened to be a Amsoil dealer. I started using Amsoil 20/50 in my 77 model Guzzi with good results.

Around 79 or 80 I started reading about guys with Triumph motorcycles that were having phenomenal results running a new synthetic brand called Red Line. This got my attention big time because before my Guzzi, I was riding a Norton. I loved that Norton, but that damn thing wore so fast it was all I could do to keep it running, spending every penny I had each month after paying my bills. I used to run Castor oil GTX w50 in it. The problem wasn't the oil though, it was the quality of the English machining and metallurgy in the early 70s.

Then in 87 I sold the Guzzi and bought my Sportster, my first Harley. Even though I knew better than to believe the crap people say about Synthetic oil I was like a lot of new Harley owners and believed that somehow Harley knew more about oil than oil company's and that only genuine Harley brand was good enough for my beloved Sportster. Harley only offered dino oil in those days and the mechanic's at the Harley shop were of the opinion that synthetic oil would make my bearing go flat and make my motor leak like a sieve. Same old crap. So everything was going swimmingly until at 28,000 miles a roller on the front intake lifter had catastrophic failure. When I tore the motor down I was surprised at how much wear I found. My faith in Harley dino oil was shattered. It might work OK up north but hot Texas summers obviously were turning it to water. After replacing every part I could find with wear I remembered what I read about Red Line and switched to it in the early 90s, maybe 91 or 92.

Since then I've been in this motor numerous times and I'm well aware of the degree of wear it's being subjected too, and I can tell you it's a lot less than with Harley dino oil. At times I do run it very hard. It spends a lot of time running 6000 plus rpm. A couple of years ago I finally spun a small end bushing on the front rod one night after a 120 mph run. It had 80,000 miles on it at the time. when It came apart many parts that had over 50,000 miles looked like new. Cam lobes, Valve guides, oil pump, and especially the high wear oil pump drive gear looked pretty darn good. The crank pin that had 80,000 miles, 28,000 with dino oil looked great.

The article at the beginning of this thread is pretty good. I've learned a little about Synthetic oil over the years and feel like adding a little additional explaination to some parts of it.


"Generally, shorter chain molecules are more volatile. Under heat, these oil components volatize or gas off, much like water boils, and leave the oil. This causes the viscosity to change among other things. A synthetic oil has less of these short chain elements. Because it is created rather than refined, the molecules are more uniform in length."

What he's says trying to say here is that natural crude oil is a soup of both short and long chain molecules, and everything in between. The long chain molecules are the best for our purposes. Since Synthetic oil is manufactured it can be made with all long chain molecules. As miles go by you motor chops up the molecules and makes them become shorter and shorter. That's why it's better to start out with all long molecules. This is one of the reasons synthetic will always be superior to dino oil, but not the only reason.


POLYESTER

Another type of base stock used in synthetic oils is ester based (diester, polyolesters,
polyesters, and complex esters). These have been tested as extremely stable under high pressures and temperatures and provide the base for oils used in some jet engines. The high end of the temperature range for these oils is 400ºF, well above the typical oil temperatures in an air cooled engine of 200ºF to 250ºF. Ester-based oils are also polar, meaning they have an electo-chemical charge that causes them to bond to metal surfaces (Wolman, n.d.). Whether this actually helps or not is a subject of some dispute.

Ester stock has the highest resistance to heat, and is one of the most expensive synthetic base stocks. If you have a air cooled motor and live in a hot climate you want a synthetic oil with a high percentage of ester stock. Especially if your motor already runs hot. What most people fail to understand about Synthetic oil is that in order to cut cost most manufacturers use a blend of various different synthetic base stocks. Usually PAO, Ester, and New Synthetic (cracked hydro). All are considered synthetic. If you blend them all together it's still 100% synthetic. The cheapest base is New Synthetic. The main way synthetic oils differ aside from the additives is the percentages of the three base stocks. In my opinion the lowest quality synthetic is the one with the highest percentage of New Synthetic (cracked hydro). The problem is most oil company's don't like to tell you what base stocks they use, or what the percentages are. Mobil one used to say on their bottle that it was a "Tri Blend Formula". Now they have taken that off the bottle, but I'm sure it's still a blend using Cracked Hydro. Harley synthetic is "Syn 3". You can bet your ass it uses cracked hydro. The truth is almost all so called 100% synthetic oils use some percentage of cracked hydro. I'm not sure about Amsoil. It may or may not have cracked hydro, but I'm pretty sure it's got PAO, and I think Ester too. As far as I know Red Line only uses Ester stock. That's why it's at the left side of the heat chart above all others.



This is Cracked Hydro

“New” Synthetic

It couldn’t be simple could it? We had it easy; either oil was mineral based or synthetic.
Nothing that simple could last; it was an area obviously ripe for exploitation. In 1984 Chevron successfully combined several processes to remove aromatics (generally lighter products) and waxes (generally heavier products) from fossil oil. These processes combined were referred to as “hydroisomerization” (Kramer et al., 2001). The ‘hydro” in this case refers to the hydrogen used in the process. Isomerization is the process where the atoms that make up a molecule are changed around to make a similar molecule with different properties (Houghton Miffin, 2000). What the hell does that mean? Synthetic oil is superior in part because of the uniform shape and size of the molecules. This hydroisomerization process removes waxes and aromatics to a greater degree than other refinement methods. It also changes some of the molecules to be slightly different, enhancing resistance to oxidization. In effect it makes petroleum oil base more
like synthetic.

Intelligent folks at this point will be thinking that this is still petroleum oil, right?
Hamburger is still beef, isn’t it? Well yes (the beef part) and no (the oil part). The National Advertising Division (NAD) of the Council of Better Business Bureaus is often responsible for arbitrating between feuding advertisers on their conflicting claims. When Castrol began to use this hydroisomerized base in its Syntec line, Mobil Oil took them to task for deceptive advertising. In April of 1999 the NAD decided in Castrol’s favor regarding the labeling of oil created from this type of base stock:

Just because your synthetic is a blend using cracked hydro doesn't mean it's no good. It's always going to be better than dino oil, and it depends a lot of what the percentage is.

I'm just trying to explain the differences between the different synthetics so you can make more informed decisions about what you're buying, and how long it might last compared to other brands, under the conditions you use it in.

I run Mobil One in my work truck and and car, and that's good enough for them, but in my beloved Sportster I only use Red Line. I admit though that the difference between Red Line, and any other good synthetic like Amsoil, is so slight that it would probably be impossible to tell any difference in the wear.

This thread started with the differences between motor oil and gear lube stating that motor oil has detergency additives not necessary for transmissions. One thing I would strongly caution is this:

The detergency additives in motor oil are not required for transmissions, but harmless.

Gear oil has moly (molybdenum disulfide) which is an extreme pressure additive to prevent wear under extreme conditions. This can be corrosive to engines or gear boxes that get hotter than 230 degrees and have copper or brass present. These additives are Not harmless if used in the wrong application!

It would be much better to adhere to the lubricant guidelines set forth by the manufacturer. If it calls for motor oil instead of gear lube then there's probably a really good reason for it. Now, as we speak, some companies like Amsoil, have GL-1 transaxle oil which is motoroil without the detergency additives and additized for transmissions. If you can find something like this to avoid the moly that would be safe. But unless the manufacturer specifies gear lube I would avoid it.

Another good point: If the manufacturer calls for gear lube, but a gear lube service rating of GL-4, make sure and use that and not GL-5 unless GL-5 is specified. GL-4 has a reduced amount of moly meaning there is a potential problem with the extra moly.

Find out first if the manufacturer is OK with gear lube before adding that to any transmission (even in cars or trucks). Then make sure that the requirement says GL-5 before adding that particular gear lube. It's the safe thing to do!

Good luck getting Harley to recommend any oil besides Harley oil. Before Syn3 they recommended not using synthetic because it would make your bearings go flat, and your seals leak. Now they would have you believe that Syn3 is the only synthetic that will work in you motor and you can use it in all the holes.

It is possible to get good information on what kinds of oil you can run in your bike. You just won't be getting much of it from Harley, except use Harley oil.

Good luck getting Harley to recommend any oil besides Harley oil. Before Syn3 they recommended not using synthetic because it would make your bearings go flat, and your seals leak. Now they would have you believe that Syn3 is the only synthetic that will work in you motor and you can use it in all the holes.

It is possible to get good information on what kinds of oil you can run in your bike. You just won't be getting much of it from Harley, except use Harley oil.

Of course Harley has been the model of contradiction on motor oil recommendation. You expect any manufacturer to steer you toward their brand. But many people think you get no warranty unless you use their brand of motor oil and that is not true. Harley themselves correct this information from time to time because of misleading information from mechanics servicing these brands. Of course, you don't get a warranty for using off-spec oil or from improper maintenance.

Synthetic base oils don't mean that all oils sporting the "synthetic" classification are additized the same or even correctly. An improperly additized synthetic can be worse than a properly additized mineral based oil. The use of quality based synthetic base stocks usually means the base oil carrying the additives is more thermally stable and has a longer service life. Usually, and I repeat the word usually, the higher cost of the synthetic base oils means that additive selection will be geared toward better performance since the cost will be higher anyway. A good synthetic is hard to beat. Doesn't mean all synthetics are good though, depending on the application. :D

How about using only Harley Air in the tires? :doh

I've read this article before. My favorite part is still the section on how oil actually provides more protection later in its life than when it is brand new. Makes me wonder how many people on this forum believe they're babying their bikes by doing oil changes every 2000 mi (or some ridiculous number like that) when in reality they're wasting money and hurting the engine.

I was always under the impression that is was the filter that wore out/clogged long before the oil had exceeded its useful life. Hence BMW's have a special (and expensive) filter that allows them to go 15,000 mi between recommended oil changes.
Cheers,
Luke

Is that why my BMW made MINI COOPER says to change the motor oil every 15,000 miles and not sooner? I always wondered what made the oil's lifespan so long.

The paper says that Syn 3 is recommended in all three cavities (two if you ride a Sporster). What hole are we missing?

Ok, so now I am confused. I changed my oil at the 5000 mile mark. My bike now has 101 miles shy of 8000 miles, and it is stored for the winter. Should I have changed the oil before hibernation even though it only has been 2899 miles? Or would doing so cause more damage to the engine and to my wallet as stated?

If I change the oil everytime it is put away for the winter then I do not need to worry about the 5000 mile intervals since it is unlikely for me to put on 5000 miles in a season. In the event that I do put on 5000 miles or more, it would probably not be over 2000 miles more than the 5000 and so I still would not have to worry about it, since I will do so at storage time.

Based on my above statement and my ridding habits, I am now deeply saddend by the fact that I don't ride as much as I would like too. :( I do so every chance I get, and that means about 4 days a week, on average, during the season. The only reason I don't ride the other three or so is either because of incliment weather here in Chicago, or because I need to haul more stuff than I can fit in my backpack, (no saddlebags yet). And the fact that I am explaining why I don't ride all 7 days probably make me a poser by some standards. :doh

good info, glad I found this before I need to change the primary.

Luisie -

BMW (and Mini Cooper) use an oil life monitor algorythym in the ECM that takes into account engine temperatures, mileage, drive cycles etc. Our Mini Cooper S doesn't burn maybe more than a quart of oil over the typically 18,000 mile oil change intervals (it's at 95k miles currently).

As for your bike, you didn't HAVE TO change the oil right before storage (probably, I mean, assuming your usage isn't considered SEVERE - not a lot of super short distance, lot of stop and go, or excessive heat).

HOWEVER your usage of 5k miles or less per year makes it the PERFECT time to do it.

As liberal as I tend to be with oil changes and my synthetic fluids I might be tempted to take your bike out of storage and change the oil, then simply keep an annual change right before storage. (FYI, I don't store my bikes, but that's what I'd likely do if I were you).

Kev

Thanks Kev M. By storing the bike I meant that it sits in a corner of the garage patiently waiting for a good weather day. I rode in December, and plan to ride as soon as the salt is gone, usually after a big rain. That could be this month or February, although in some years it has been as late as the end of March/early April.
Thanks for sharing your knowledge and always answering me.

Sounds like you store like me...

...when you get those winter rides, try to make sure the oil comes up to temp.

If it often does not, that's another reason to consider an early change.

RIDE SAFE!

Kev

How about using only Harley Air in the tires? :doh
That might be a good idea for Harley. Helium! Would make the bike a little lighter, right?:p

Of course I'm joking. That would leak like crazy!:smoke

They put Nitrogen on my tires and they even have chrome valve stem caps with a green top, to indicate that there nitrogen. No charge to me "Prefered Customer", otherwise about $30.00US.

What I was suprised to read was not to change your oil as often and under normal conditions it's better. Maybe the younger guys can wrap there heads around it better than I do. I've always changed my oil at the 2500-3000 mile mark in the car, bike, RV thinking it was best, even thought the owner manual states different. I'm not entirely surprised that the HD oils the MOCO states we should use isn't good stuff. Thats what I use and for the type of riding I do it's been good to me. I guess all companys bottom line is the all mighty dollar, Harley being no different. We trust them when it comes to our choice of motorcycle, why not there judgment when it comes to the fluids to use in them and the frequency of fluid changes.

Believe it or not, I was a 2,000 mile oil drain person before and had a hard time wrapping myself around extended drains. Why? Because used oil samples back in the 80s came back showing the oil was not suitable for continued use at 3,000 miles. I sent in many sample hoping to find that "sweet spot" where oil was still good and it seemed that samples around 2,500 miles use tended to be borderline depending on what type of driving people were doing. So I settled on the 2,000 mile for myself. Specifically, the TBN additives were depleted at 3,000 miles and the rules say to drain when the TBN number is 2 or below at that time. I want to clearly state that petroleum oils today tend to last longer and I've seen samples with 4,500 miles that passed with good TBN numbers. I'm pointing out what we saw in the 80s.

I came across some people selling synthetic motor oil claiming 50,000 mile oil drains which hit me as being impossible. That company was a new and little one and no longer in business. Oil sampling showed their oils good to 20,000 miles which surprised me a lot. However, their oil bottles had a brown sludge in the bottom. I asked about that and was told, "Those are additives that have settled. Just shake it up and pour it into the engine." I did NOT take that advice and took a sample of the brown stuff and sent it in for analysis. Lucky I didn't add that to my engine as it turned out to be a combination of sand (silt) and rust (iron oxide). In other words, they were sloppy in the bottling process.

Later I came across AMSOIL and they seemed to have better experience. Of course considering how hoaky the last guys were I did some motor oil sampling and my engine oil passed every sample up to the 25,000 mile oil drain limit. I was driving in excess of 25,000 miles in one year so the limit came within the year time limit on my vehicle, a '79 Mitsubishi pickup 2.6 liter. I changed the oil, but later found out any company including AMSOIL will warranty the oil beyond the limit if used oil sample verifies oil condition. I had to conclude something was very different with those type of synthetics compared to the petroleum oils and adjusted my oil drain interval based on that. I also want to mention I later began to drive that vehicle in excess of 100,000 miles per year in a new business. I had little money and could not afford mechanical problems especially if expensive at that time. I took a chance and did sample at 25,000 mile intervals which was less often than before and never did a sample fail. I sold the truck in superior mechanical condition at 330,000 miles for a larger vehicle to use in this business. It never needed any attention other than routine maintenance including brakes, clutch, tune-up. I remember changing ball joints and link pins also. It was never involve in a motor vehicle accident (thank God!) and tires tended to last to around 80,000 miles. Considering how rarely I changed oil I spent virtually nothing on it.

So when you mention fear of extending oil drain, I'm know the feeling. Hard to feel comfortable running an engine that could have "liquid sandpaper" flowing about. If you want security, take a sample of the oil you are throwing out. If it's in excellent condition you can "fudge" some later and go a bit farther safely. Also, if you have any mechanical problems that should show up in the oil sample too. :)

has anyone seen the synthetic oil commercial with the little bearded red head guy slapping people with a dipstick for"not thinking with there dipstick" this thread reminded me of it. but anyway this should be a sticky. good info to know. and thats thinking with your dipstick jimmy lol

So what gear oil should I use in my Harley? I always had difficulty finding neutral from the word go on my 883 sporty (2003) model. It also really graunched when going into first gear, so I start her up in gear. I have since opened her up to 1200cc and triked her, so I've increased the amount of clutch plates to take the extra load. Still clonks and the only way to get her in neutral is to coast and tap her in from 2nd, it is impossible to get her into neutral from 1st unless I stop the engine. Would a lighter oil help in the gearbox? I keep the clutch adjusted as per the H-D manual. So would a synthetic oil help? The oils that you talk about are local to your country, but I live in the UK, so oils could be different, but I can get synthetic oils here but not the ones you talk about, such as that Amsol and Redline.
,

The oils that you talk about are local to your country, but I live in the UK, so oils could be different, but I can get synthetic oils here but not the ones you talk about, such as that Amsol and Redline.
,

Hi Dave !

Please look here : http://www.performanceoilsltd.co.uk/ (http://www.performanceoilsltd.co.uk/)
They have Amsoil.

And this one sells Redline oil : http://www.opieoils.co.uk/c-413-redline.aspx (http://www.opieoils.co.uk/c-413-redline.aspx)

Good luck and ride safe !

Hi Dave !

Please look here : http://www.performanceoilsltd.co.uk/ (http://www.performanceoilsltd.co.uk/)
They have Amsoil.

And this one sells Redline oil : http://www.opieoils.co.uk/c-413-redline.aspx (http://www.opieoils.co.uk/c-413-redline.aspx)

Good luck and ride safe !

Thanks Erik for the info, I think I'll give that Redline a try; just as a matter of interest; what are you using in your Sporty, after all your hard work on her? :D

I've read this article before. My favorite part is still the section on how oil actually provides more protection later in its life than when it is brand new. Makes me wonder how many people on this forum believe they're babying their bikes by doing oil changes every 2000 mi (or some ridiculous number like that) when in reality they're wasting money and hurting the engine.

I was always under the impression that is was the filter that wore out/clogged long before the oil had exceeded its useful life. Hence BMW's have a special (and expensive) filter that allows them to go 15,000 mi between recommended oil changes.

Cheers,
Luke
20-50. anything, on sale. Change every 1000-2k mi. Filter, every other change. To many miles on bike for synthetics. To slick. Leaks different:))

Thanks Erik for the info, I think I'll give that Redline a try; just as a matter of interest; what are you using in your Sporty, after all your hard work on her? :D

Hi Dave ! You're more then welcome. All's well ?

I use Bel Ray SAE 20W50 #96605 as an engine (Dino)oil, and HD Formula+ as primary oil.
http://www.mijnalbum.nl/Foto-Z4LY8YST-G.jpg

http://www.mijnalbum.nl/Foto-WFODTJXO-G.jpg

http://www.mijnalbum.nl/Foto-ISRMQ4E6-G.jpg

Very good read. I saved the article and will pass it on.

So what gear oil should I use in my Harley? I always had difficulty finding neutral from the word go on my 883 sporty (2003) model. It also really graunched when going into first gear, so I start her up in gear. I have since opened her up to 1200cc and triked her, so I've increased the amount of clutch plates to take the extra load. Still clonks and the only way to get her in neutral is to coast and tap her in from 2nd, it is impossible to get her into neutral from 1st unless I stop the engine. Would a lighter oil help in the gearbox? I keep the clutch adjusted as per the H-D manual. So would a synthetic oil help? The oils that you talk about are local to your country, but I live in the UK, so oils could be different, but I can get synthetic oils here but not the ones you talk about, such as that Amsol and Redline.


This problem is more likely related to improperly adjusted clutch or warped clutch plates, or the clutch lever, or something else in the mechanism, does not have enough throw to completely release the clutch plates. If all is in adjustment, even the worst oil will not cause these problems, unless it has turned to mud.

When hot, she goes into gear easiy enough, and the take-up of the clutch is just before the lever is let out, so, no problem with the movement and adjustment. If the engine is off, I put her in gear, pull the clutch in and I can move her quite easily. I normally free the clutch that way when getting the bike out, but she has always been clunky going into 1st gear when cold, so much, that is I start her up in gear, and getting neatral from 1st gear was always hard, normally a light tap as I was coasting to a stop from 2nd did the trick and then just a lightest of taps would get her neutral, again from 2nd, if stopped. The difference between my MZ and the Harley is unbelievable, on Emmy, I stop, whether in 1st or 2nd, just a tap and neutral, no problem, anytime and everytime!

If you are sure the clutch is adjusted properly, try a good synthetic designed for wet clutches and motorcycle transmissions. I would not try anything but the reccommended viscosity. See what happens. If the tranny oil you are using is getting too thick at lower temperatures, a good synthetic shouldn't have that problem. All you can do is try it and see. If you still have the problem, something else is wrong. Is primary chain tension correct?

If you are sure the clutch is adjusted properly, try a good synthetic designed for wet clutches and motorcycle transmissions. I would not try anything but the reccommended viscosity. See what happens. If the tranny oil you are using is getting too thick at lower temperatures, a good synthetic shouldn't have that problem. All you can do is try it and see. If you still have the problem, something else is wrong. Is primary chain tension correct?

I've just fitted a Hayden M6 chain tensioner, supposed to make things smoother, out on the road it seems smoother, but going into 1st gear when cold, very clunky as before! I will order up some synthetic tranny oil and give it a try.

I just did a complete LUCAS motorcycle oil change on my 84 Iron head...20w50 synthetic with a 1/2 quart LUCAS oil stabilizer...I had to turn the idle down a little, it seemed to raise about 2 or 300 rpms more....I haven`t put but 5 miles on the oil change....I figure I`d check it out since my buddy is sponsored by LUCAS and gets his oil for nothing...He gave me a case of it to check out....

I've just fitted a Hayden M6 chain tensioner, supposed to make things smoother, out on the road it seems smoother, but going into 1st gear when cold, very clunky as before! I will order up some synthetic tranny oil and give it a try.

I believe it was NRHS that said beware the M6 chain tensioner because it may detonate and leave parts to complicate things. I think they saw it wear very quickly.

Edit:
I found it on their site, here's the NRHS link
M6 Primary Chain Tensioners for XL's (http://www.nrhsperformance.com/tech_xlm6.shtml)

I am a chemical engineer by training, so I really enjoyed that paper. It is very hard to sift through the marketing spin with oils.

The first main lesson for me was that both of the HD oils are reasonably different from many other types of oils. Since it is difficult to know what matters and what does not, I will pay a slight premium to stick with the HD product. However, the two HD oils, (20w-50Syn and 20w-50petroleum) are very similar oils. Since the synthetic is twice the price, I will never use it.

Second, frequent oil changes (<3000miles) are worse for an engine than less frequent (~5000miles) changes. This was surprising. I had always believed newer was better, but I am glad to be corrected.

Lastly, sport-trans in the tranny, HD20W-50 in the engine. They have different functions and formulations to match that function.

Not sure how many of you will find this helpfull but I have a powerboat with a little hot rod sbc in it. I visited the forum below a ton in the past. If you want to read some of THE BEST INFO YOU CAN FIND on oil I would suggest giving it a try. LOTS of good info....Picture pulling 10,000 pounds up a hill in 2nd gear instead of first...Well thats pretty much what a boat does all day long and in a HP powerboat that might be at 3500-5000rpms...All this in a motor that probally costs AT LEAST as much as our sportys! Anyways lots of good info maybe you all will find it helpfull......

http://www.offshoreonly.com/forums/general-q/107808-marine-lubrication.html

I've just fitted a Hayden M6 chain tensioner, supposed to make things smoother, out on the road it seems smoother, but going into 1st gear when cold, very clunky as before! I will order up some synthetic tranny oil and give it a try.
Well, I read an article about the M6 and I wasn't happy, so I checked out the primary chaincase and the tensioner, there was wear on the metal side already, so I removed it and put the original tensioner back on, washed out the gearbox and primary area and refilled with semi-synthetic oil. Things are a lot easier, can get into 1st gear and I can find neutral again. Talking to and indy Harley mech and he says the M6 is ok for the BT's, but not great on the Sportsters. The gearbox was always clunky from when I got it, you'd think HD would take a look at Jap technology and do the same for their own m/cs. My old East German MZ is 26 years old and basically the same gearbox as the Super 5 that it replaced which goes back to the old prewar bikes, and it has a far superior gear selection!

http://i4.photobucket.com/albums/y148/1961littledave/MZ250-2.jpg

I agree. the only way to kno exactly how often to change your oil is to have in anylized and it would be different fro engine to engine. Ive seen psted on car forum sites that soe people only change the filter and add oil.

I filled the tranny with a semi-synthetic oil 75-90 weight. I went across to Scotland last Friday to a rally, well loaded down with gear, and the selection was much easier, even could get into neutral from 2nd, still virtually impossible from 1st unless I stop the engine. But, hey things are a lot better!:clap

willprevale makes some interesting points:

who says dino oil is no good. i have seen marine engines with over 200,000 hours on the oil and still chugging along. now before you start screaming let me say the the sump capacity is quite large, the oil is temperature controlled and most importantly it is centrifuged. matter of fact, the oil is not changed unless the oil analisis calls for it.

oil gets dirty and the additives wear out but the base is still good unless it is destroyed by heat or contamination. the oil is made up all the time as an industrial engine can use several gallons of oil an hour so the additive package usually stays up. honda used to incorporate centrifugal oil cleaners on their machines but switched to the paper throw away filter like everyone else. the centrifuge can get to the sub-micro area but usually 1 to 2 microns is the norm.
there are different bases for synthetic oil, each with its own advantages so make sure you use the base stock that will apply to your requirements (btw: synthetic does not mean that dino base is not used). there is an advantage in flow characteristics. if you take a box with "x" size hole and put round balls into it that is uniform in size and will pass through the hole, you will have better flow than multi-sized balls trying to bunch up and go through the hole. synthetics are engineered to be molecular uniform unlike dino oil.

for the everday driver, dino oil is a good bargin. however, i do not recommend auto oil but oil for the diesel engine because the base stock is better and the additive package is better. it's all that is used for the last ump-teen years, buy it in the drum. but to each his own. yes, i have tried the synthetics but do not find them any better for my type of service.

i have an 05 sportster custom and an 08 nightster do these use a diff oil in the primary? i am seeing people say they do on thiers i didn't think the evo did. this would be a good bit of info to know. i feel very very stupid at the moment.

i have an 05 sportster custom and an 08 nightster do these use a diff oil in the primary? i am seeing people say they do on thiers i didn't think the evo did. this would be a good bit of info to know. i feel very very stupid at the moment.

For years Harley sold Dino oil for the motor and a separate formula dino oil for the clutch/transmission called "Sport-Trans"

When they came out with Syn3 they said it could go into both holes.

Some people use M1 V-twin or Amsoil in both holes too.

Some people use gear oil (like M1 75-90 in the clutch/trans).

Don't forget H-D Formula +, which, as you know, is the newer spec lubricant that replaces the old Sport Tran lube for Sportster gearbox/chain cases.

Any words or Royal Purple or Lucas Oil 75/90 for trans lube?

I've done just under 3,000 miles since last oil change,going to just change the filter this time and top up, change at 5,000. My diesel car, says 10,000 between changes, how come so long, when diesel dirties the oil more than petrol?

I've done just under 3,000 miles since last oil change,going to just change the filter this time and top up, change at 5,000. My diesel car, says 10,000 between changes, how come so long, when diesel dirties the oil more than petrol?

Particulates aren't usually an issue when it comes to oil.

Contaminants (acids etc) are more an issue. And they are formed or NOT based on operating conditions (which though diesels aren't gentle on their oil they are not as harsh as air-cooled motors). Tighter tolerances and better controlled combustion/operating temperatures make diesels better on oil.