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Synthetic Oils


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Much talk about Syn 3 from the Harley dealers. Let's talk a bit about that oil and it's application

SYN3 is a group III synthetic oil.
Group III synthetics are called hydrocracked isodewaxed mineral oil. In english all that means is that it is dino oil that has been super refined to meet the specs of a low grade synthetic. Group III's do exibit some of the qualities of synthetic like more uniform molecules, higher shear resistance to name a few, but will not stand up to the higher temps in todays motors.
I have never used SYN3. It's produced by Citgo, a Valenzuela company who contracts to whatever oil company will make SYN3 and then slap a HD sticker on it.
Harley Davidson is in the business of making money, not oil.

With that said, the synthetics that are also being discussed here, Mobil 1, redline,Royal purple and a few others are group IV Synthetics and contain no mineral oil at all. They are typically PAO's (Polyalfaolifins) and are 100% man made. Therefore they contain no contaminates that are commonly found in petroleum base stocks. Their resistance to thermal breakdown is well recorded and one of the biggest benefits of a synthetic, and also your engine.
Synthetic oil does not burn like a petroleum oil therefore leaves no or little deposits on your internals, also a benefit to your engine. A synthetic oils lubricity is far superior to petroleum oil because of the uniform molecules, so you will have less wear and cooler running temps, usually in the 10*-15* range.
All good reasons to use synthetic oils. If you change your oil as recommended by petroleum oil companies, 2500-3000 miles you are changing the oil after its useful life has ended. That means at least for some period of time, your dino oil was not doing the job it once did when it was new. This is where the benefits of a synthetic come into play. In most cases the wear and tear being caused by spent dino oil will not be realized until you experience a mechanical breakdown. Your engine will run strong, sound fine, even with scored bearings....until they fail. If you can take documented science and apply it, knowing that a synthetic is causing less wear, cooler running conditions, cleaner running conditions and therefore longer engine life, there is no better reason to use a quality synthetic oil.

I also wanted to address the issue of the oil appearing "dirty" quickly. This can be caused by several things. Residual oil in the sump and oil galleries at the time of an oil change, excessive engine wear, blow-by that could be caused by worn or sticking rings, inferior film strength of the lubricating oil on the cylinder walls, dirty or inefficient air filtration. All good reasons to look at a quality synthetic oil to use in your bike.

Also see these posts about Syn 3 Oil...

Syn 3 MSDS - Harley Davidson Community

Oil Groups Explained - Harley Davidson Community
Glider, after extensive research on engine oils I have decided to run spectro in my 2011 Heritage. Most of the comparative performance studies I have seen on the oils, especially, the synthetics are a little dated. The oil companies constantly tweak the additives. For example, I recently found out Harley has reformulated Syn3 in the past 18 months And it is alledgidly now a true synthetic. I think it would be interesting to see recent and comparative oil test results between Mobile 1, redline, amsoil, electro & Syn3. Are you aware of updated studies on these oils?
Ride 2004 Ultra with upgraded 103 screaming eagle motor & 6 speed screaming eagle transmission , i run amsoil in all 3 holes - 20W50 in oil & primary reservoirs & SAE 60 in transmission & could not be happier with the performance & endurance of Amsoil !!
Just changed oil yesterday. I decided to go with synthetic SAE 20/50. I have always used Castrol Oil in my cars and it has never let me down. At Autozone I found Castrol Power RS V-Twin 4T for Harley Davidson Motorcycles it is a full Synthetic and with only about 90 miles since the change, I'm happy! I have a 21,800 on the Sporty and I will post any problems that may come up.
When I changed to Mobil 1, in all 3 holes, from Syn3. I noticed less lifter noise and no more compensator clatter.2014 compensator sounded like a bucket of bolts at idle with Syn3.
When I changed to Mobil 1, in all 3 holes, from Syn3. I noticed less lifter noise and no more compensator clatter.2014 compensator sounded like a bucket of bolts at idle with Syn3.

Spelled SIN3

Now you have GOOD Oil and a GREAT Candidate for Pres...

Can't beat that can you....:51::51::51::51::51::51::51:

Does Mobil 1 have a "motorcyle" oil like Amsoil, or is all one Mobil 1?

My 13 Ultra did not like the Amsoil. Very noisy upper engine noise that quieted when I used Syn3
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Mobil 1 does make a VT Mobile 1. It is available at Auto Zone. That is what's shipped with a new S&S motor.
I have been using Mobil 1 V-Twin in all 3 holes on my '09 Ultra for the past 5 years now. Motor still runs great, never have to add oil between oil changes.