LS type motors likely use plain bearing cranks. HD use roller.

 

I knew that...dont know why I brain cramped on that.

BUT it still shows how a certain micron filter IS important.

 

I'm sure it is but at what number does it become important?

 

http://www.baldwinfilter.com/TechTips201403.html

One can argue roller bearings needs less pressure, plain bearings need more
What needs a better purge?
Poured or plain style babbits will to a point accept FOD and be embedded in the shell.
Rollers OTOH will not do that.
They take the hit and steam roller over the debris, collateral damage.
SO.....perhaps that might be the biggest reason to keep HD smaller micron filters rather than an acceptable larger micron number.
Looks like HD recommends around 5 micron too

https://accessories.harley-davidson....lters-5-micron

 

Absolutely.. Any kind of flow is all a needle/roller/ball needs and not much. None of those are pressure fed in HD. If talking flow, needle/roller/ball could easily get more flow even at drip rate feed.

 

yea, for a long time i just always thought most any POS oil filter on a HD is gooder enough.
But, one of those nights in deep meditations about valves glowing red hot,
40 or 50 lbs of iron spinning between my legs,
The carnage from Sgt Maj General- ( Pirates of Penzance )
I got to thinking about the road the roller bearing have to travel!
There is nothing very forgiving there.
Simple? yes!
But Shell types have more EZ life as they are not actually contacting the crank. (at least in theory)
The HD engine is a contact plug fit assy .
So the light went on in my head and said , "my oil and filter should not be as barnyard I thought it to be !

 

Deep stuff. Good thing HD don't use the oil "horsehair" filters anymore. I'd figure whatever made it through was iron, softer steels. aluminum, or maybe a little carbon. Some may have an effect but likely act more as a cushion. Less filtering, your can always change you oil more often..

 

I call BS on that being a 5 micron filter... or at least 5 micron at a commonly accepted rating standard. Maybe 5 micron at nominal rating.

Amsoil full flow filter does 20 micron at 98.7% absolute is about the best on the market. Even the stainless media filter that was originally being discusses claims only 35 micron absolute.

To get into a 5 or less micron filter from Amsoil you end up in their by-pass filter line. Their by-pass filters will do 2 micron at 98.7% absolute but can only handle 10% of the flow of a full flow filter. I believe the by-pass filters are manufactured by Donaldson filters.

So back to harley's 5 micron "claim", I dont buy it since a 5 micron, 98.7% absolute filter would suffer in the flow department and be a huge bottle neck in a full flow oil system. Unless of course it was always trigger the pressure relief, which defeats the whole purpose of a filter to begin with.

 

I know a few things, not everything, and am partial to Amsoil products.
I will say I have not studied filters and all that comprises of them
It was asked about micron and i posted a couple links.
The first link shows what size a micron is.
I for certain am not advocating anyone's oil or filters.
i always tell people to do their own research.

 

does any of this REALLY matter in real World application? do Harleys not enjoy trouble free long life expectancy because of the oil filters they use..which are basically the same exact ones for the last 20 years...haven't they proven to be plenty good enough at this point..guessing around 90% of the millions of bikes on the road over that time use OEM with no downside