synthetic oil question...

[DevilDawg1]

Originally Posted by lightguy

The majority of wear comes at start up when the bearings are "dry" and there is no oil pressure or more importantly; flow. This is why low weight oils are best for most engines; its all about flow. I use 0-40 in my twin turbo Audi and everything else I can. If Harleys tolerances are real sloppy perhaps a 5-XX or 10-XX weight.

" As the engine build heat the viscosity thickens thus the high end of the stated weight. Multi vis oils automatically adjust."


If you want to get picky even 0 weight is too thick on start up for most every internal combustion engine made today.
Sounds crazy but thats the way it is.
If Harleys had hydraulic lifters there might be a reason for thick oil if they were engineered for it. AFAIK they use solid/roller lifters (?)

I could be wrong here, but most oils get thinner as they come up to operating temperature. And when the oil is cool (setting over nite), the thicker it is.

20 w - no thinner than 20w when heated to a certain temperature
50 - no thicker than a 50w when cooled to a certain temperature

These are the very basic meaning of the numbers.

[eagle1]

ck out red line shockproof syn gear lube. syn 3 is waaaaay too thin for a tranny.
also r/l makes the only 20x60 syn motorcycle oil that i can find. i get mine at
harproworld.com

[bikedelic]

Originally Posted by Dave63

Yes.....this would be true, if... Where are you getting your information from?...

Thanks Dave for a necessary reply. I was tempted but yours was much more qualified.

[Cadivillellac84]

Some people are going crazy about oil. Here is an example I went to Cuba last December and I spoke to Owenrs of pan heads and shovel heads and even modern Harley's there but mainly the old school bikes from 50's and they say they use WHATEVER oil they can find and pour it in. I am talking about bikes from the 50's and they still on the streets with no problem. So just change your oil often and make sure you put oil again don't just run with out oil. Just saying


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[Dave63]

Originally Posted by Cadivillellac84

Some people are going crazy about oil. Here is an example I went to Cuba last December and I spoke to Owenrs of pan heads and shovel heads and even modern Harley's there but mainly the old school bikes from 50's and they say they use WHATEVER oil they can find and pour it in. I am talking about bikes from the 50's and they still on the streets with no problem. So just change your oil often and make sure you put oil again don't just run with out oil. Just saying


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And what condition are they in, and how many times have they been rebuilt?

Comparing a flatty/Pan/Shovel to an Evo or TC engine is like comparing a Boss Hoss to a Big Wheel.

Pans and Shovels use 60 or 70 wt oil. No multi-visclosity oils. In severe cold, you can run 30wt. Not gonna see that in Cuba.

You can run straight weights in Evos and TC engines but the tolerances and oiling is improved far beyond older engines, now allowing multi-viscosity oils.

Its not "going crazy" about oil, rather being properly educated and understanding why the manufacturer recommends one thing, and using something else to save a few pennies may not be the best idea or a well informed decision.

Yes, you could run just any old oil in your engine. However, I'd be willing to bet money on a decreased longevity. Using anything not rated for an engine is never a good idea.

[Cadivillellac84]

Some were like brand new out if the dealer and some were in bad shape and trust me the ones in bad shape u could tell haven't been rebuilt in many many years. There is no parts in Cuba for Harley Davidsons.


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[Cadivillellac84]

Google pics of Harley Davidsons in Cuba


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[lightguy]

Originally Posted by DevilDawg1

These are the very basic meaning of the numbers.

"This is the very basic meaning" or "these are the very basic meanings"...
of the number(s).
I want to be quite sure since we are picking nits.

[DevilDawg1]

Originally Posted by lightguy

"This is the very basic meaning" or "these are the very basic meanings"...
of the number(s).
I want to be quite sure since we are picking nits.

No matter which way you slice it.

[rossn2]

20 w - no thinner than 20w when heated to a certain temperature
50 - no thicker than a 50w when cooled to a certain temperature

Don't think so...

20w-50 oil flows like a 20w weight cold and once at normal operating temps has the characteristics of a 50w oil due to the add pack. It is 20 weight oil no matter what temp the oil is...

So those who run 5w-50 oil have 5 weight oil in the scoot no matter what temp the oil is..just saying!