The HD OEM filters and aftermarket paper filters are rated on averages, percentages and multiple passes. ¹⁾
So a 10-micron-rated paper filter may be letting particles 100 microns and larger through.

All of the different brand of reusable filters below:
Are 30-35 micron 'absolute' stainless steel mesh material.
(this means nothing smaller than 30-35 micron should get past them).
Advertise that they are the last filter you'll ever need.
And seem to be basically the same filter other than cosmetics.

Fitment: 86 and Up Sportsters:

Features and Specs:

• Constructed of laser-cut, medical-grade, 304 stainless steel micronic filter cloth
• In many cases filters provide 200% more filter area
• Stainless filter catches items down to 35 microns
  (about three times better than most good paper or brass filters))
• Pleated seam is welded and able to withstand up to 600 degrees
• Maintains consistent flow under all conditions including extreme heat, the presence of water, and cold start-ups
  (where paper filters can flow so poorly that they often cause the bypass valve to open and allow unfiltered oil to enter your engine)
• Widely used in all types of auto racing including NASCAR, Indy type cars, Formula 1 and in the Aerospace industry
• Weight (.80 lbs)
• Colors:
  • Black (PCS4B) ²⁾
  • Machined aluminum (PCS4C) ³⁾
  • Replacement sealing O-ring (Z-065) ⁴⁾

⁵⁾

FLO reusable oil filter 6)

FLO reusable oil filter 7)

Black powdercoat available as an after purchase cost.

⁸⁾

The bypass is on the bottom side of the element. ⁹⁾
The little ball inside is spring loaded as in the pics below.

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Features and Specs: ¹²⁾

• Cleanable, reusable, forever
• Surgical-grade pleated stainless-steel woven media filter element
• 30 micron absolute filtration
• Superior flow characteristics
• Preserves horsepower by reducing load on pump
• Built-in rare-earth magnet captures ferrous debris particulates
• Quad-seal o-ring offers improved sealing characteristics and requires less compression for sealing
• Standard sized hex boss is pre-drilled for safety wire
• CNC-machined billet aluminum body with titanium-color anodized finish anodizing and knurled no-slip grip.

K&N SS-171:
A K&N reusable oil filter by Pure Power.

Features and Specs: ¹³⁾

• Lasts the lifetime of your vehicle under normal vehicle operating conditions
• Dual woven T-304 stainless steel micro-screen filtration
• Reusable Oil Filter
• The filter housing, bypass valve and call plate are CNC machined from billet 6061 T6 aluminum
• Embedded Neodymium Magnets
• Substantial increase in oil flow when compared to standard disposable oil filters

The Outlaw is a high performance, reusable oil filter.
At the heart of the filter is a medical grade 304 stainless-steel micronic cloth filter designed to pass a large volume of oil when compared to standard paper filters. ¹⁴⁾
The cloth is designed to filter out particles 35 microns or larger.
(35 microns is below the limit of human visibility)

Medical grade stainless steel cloth is consistent across the entire surface.
And when rated at 35 microns (meaning nothing larger than 35 microns will pass through the material),
It is an absolute. But with paper filters, the rating is an average.
Additionally, paper filters have a bypass, so on startup & high RPM the oil is not being filtered at all.

Regarding horsepower increase: ¹⁵⁾

We have done tests on multiple Twin Cams, and always seen an increase in RWHP & torque.
We have also tested a couple of Sportys and have not seen significant gain in RWHP & torque.
Although we have had reports from others that they have seen an increase on Sportys,
We've not seen it on the couple we've tested. Twin Cam and Evolution motors are significantly different.
However, on start-up and high RPM the paper filters go into bypass mode.
That means there is no filtration happening at start-up and most importantly, at high RPM.
The added benefits of a pre-filter magnet, some cooling benefits along with better filtration are worth it. Plus, less garbage going into landfills is a not a bad thing.
Also, if you ride a lot, in the long run, there is a financial savings to not buying so many disposable oil filters.

Fitment: 86 and Up Sportsters:

Features and Specs: ¹⁶⁾

• Cleanable and reusable
• Meets or exceeds manufacturers specifications
• Medical grade 304 stainless steel filter flows 7 times more oil than a paper filter
• Reduced oil pump drag = increased power to rear wheel
• Provides faster oil pressure at startup
• Billet housing fins help drop the temperature of the oil via heat dissipation
• Integrated magnet pre-filters the oil
• Reduces / eliminates bypass of unfiltered oil found over standard paper filters
• Pressure tested to 1000 psi.
• No more cutting apart filters for inspection
• Environment friendly
• 17 mm wrench nut drilled for easy removal, includes safety wire hole required at most race tracks
• There are two quad rings included.
  A quad ring will typically last 3-5 oil changes.
  Additional quad rings are available.
  If you accidentally damage the stainless steel element, those are also available.

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