Ran across this— an incredible study on various oils and their performance. Included in the study is failure analysis of roller lifters and a comparison to bushing rollers.
It’s a very long read but worth the effort IMO.
https://540ratblog.wordpress.com/201...-test-ranking/

 

WOW....

Quite the read. Need something like this to ride out the blizzard we are currently having... I'm only 2 1/2 hours into this article and didn't even get halfway through it.. Yea it's a long one. Started skipping around and found that my oil that I use in my 98 fatboy w/stroker 96" motor wasn't even tested (pennzoil 25w50 conventional)..
What I did find that according to this article the best oils for wear protection and high temp are the 5w30 full synthetic oils (not the blends).

Motor Oil “Wear Protection” Ranking List – which is determined by each oil’s film strength/load carrying capability/shear resistance psi value, that results from being subjected to a dynamic friction test under load, at a representative operating temperature. He used oil temps of 230* and also on certain oils he tested to 275* and their amount of breakdown in percentages that still performed very well.. or should I say in his outstanding class that most oils (20w50"s) can even provide at 230*..

One thing I'm starting to believe is that Zinc and ZDDp are not the base for protection and too much can cause less protection than you might think, according to this article...

Based on what I have read I would like to go to a 5w30 full synthetic but all I've ever heard was that synthetic oils are not good for older evo's. But lets take a look at our "Air Cooled V-Twins" especially our built "Air Cooled V-Twins" (more heat).

After a little mor research I think i'm gonna try this oil, 0w40 Mobil 1 FS the rating for it follow.
0W40 Mobil 1 “FS” European Car Formula, ACEA A3/B3, A3/B4, API SN, synthetic = 127,221 psi
This new oil replaces the older version called, 0W40 Mobil 1, European Formula, API SN, synthetic. See below for the older version’s ranking position.
zinc = TBD
phos = TBD
moly = TBD
This new “FS” version was tested in Summer 2016.
However, a 40wt hot viscosity rated motor oil is too thick to be ideal for most engines. It is best to select the thinnest motor oil viscosity that will still provide acceptable “hot” oil pressure. And you do NOT need to select the “highest rated” motor oil, just as it comes right out of the bottle, from this Wear Protection Ranking List. There are many highly ranked oils here, that will provide your engine with excellent wear protection. So, you have many oils to choose from.

I also went on to test this oil at the much higher temperature of 275*F. At that elevated temperature, any hotter and thinner oil is expected to experience a drop in Wear Protection Capability. This oil did have a 16% drop in capability. But, even at that elevated temperature, it produced an impressive 106,876 psi, which still kept this much hotter and thinner oil in the INCREDIBLE Wear Protection Category.

I also tested this oil to find out its onset of thermal breakdown, which was 280F.

The above outlined in red is as quoted from

"540 RAT – TECH FACTS, NOT MYTHS

• Q AND A

MOTOR OIL ENGINEERING TEST DATA

by 540 RAT "

Would love some feed back on my choice, Thanx....

 

0w40 in a twin cooled Harley?

 

No, I'm going to try it in my stroked 96" Evo. It's a 98 Fatboy...

 

He originally posted it on speedtalk. They attacked him from every angle on his testing methods. You might be able to find that thread over there. Makes for more interesting reading.

 

The only thing's I really got out of this, is, Zinc ain't all that. Change your car oil every 5,000 miles, no matter what. And change your motorcycle oil every 3,000, unless you beat it up regularly. Then it's every 2,000.

 

I do realize that his article was primarily about flat tappets and spring pressure wiping out cams. Are we not in the same direction with 320-340 lbs on our lifters and cam. I do realize that we also use roller lifters and I have seen on some of my cams and others out there what looked to be the start of galling. What makes it more sensible is that we're running air cooled motors. I don't see any harm in running an oil that will give better protection at higher temps. How many times did you have to shut down your ride because the temp got so high that the oil pressure went to **** and the lifters lost their prime? Clackity Clackity clack...... Wont hurt to check it out....

 

I mean, I feel ya, as oil is cheap and cheap insurance, but...... I've done 5000-15000 mile synthetic oil changes on my 2000 toyota. It has 286K on it. Never used a drop of oil. I've done UOA's and oil has been good at 15K. Granted, this is mostly highway mileage. My bikes have been changed between 3-6000K miles. Syn and dino. UOA's good. I don't baby my bikes or cars either.