Since these types of filters are not popular but come up in posts once in awhile I figured I'd get some info straight from a manufacturer. I emailed Dave Fisher at K&P Engineering, who makes the filters sold by Scotts for motorcycles, asking about beta ratios and how their SS mesh filters stack up to a paper filter.
I also asked about cleaning the filter and the idea that tossing in a fresh "clean" paper filter eliminates the posibility of reusing a contaminated filter from improper cleaning technique.
This is a portion of the response from two emails:
(I have Dave's permission to post them)
The only way to compare the filter media directly to each other is to run them through the same test at the same time. I haven’t found anybody who could explain to me how you can scientifically use two different beta ratios to compare media, even though it is commonly done. Basically, throwing out a number at some percentage of efficiency just sounds good from a marketing perspective. Actual media performance is much more complicated. And there are plenty of white papers out there on the different theories. On top of it all you’ve got the media’s consistency factor as well as bypass operation and bleed by helping to complicate the subject.
In order to compare the baseline filtration of filter media we use the ASTM test which eliminates percentages, averages, multiple passes, and all the other variables the SAE tests allow you to introduce. From the side by side lab tests we have had done, we meet or exceed the filtration performance of the factory filters. You may or may not want to take our word for it, after all we are a manufacturer and this could all be marketing jargon.
When we run filters through the ASTM test, the paper filters (even the ones with 10 microns on the box) will actually pass particles ranging from 45 to 90 microns. The stainless cloth we use doesn’t pass anything larger than 35 microns (it actually tested at 17 microns). So yes, we meet or exceed the filtration of the factory filters as well as other (aftermarket) replacements.
We feel the real benefits of the filter are in the increased flow of the filter media, reusability, ease of inspection and reduced environmental impacts.
Remember that the stainless steel filter flows many times more than a new paper filter, so even if the ss filter is 50% plugged with debris, it will still flow around twice as much oil as a new factory filter.
It is nice to believe that a new, fresh paper element will give you the best starting point for cleaning your oil. However, think about the cellulose particles that may not be totally attached to the paper mat (either in glued or pressed construction). Not a problem with our ss filter. Think about any dust and dirt that may have gotten into the filter during manufacturing, packaging, shipping, customers fondling the product on the dealers shelf, etc.. At least with ours, you can clean it prior to use to make sure it isn’t introducing any of that material into your engine (like you would with any other critical engine component). To substantiate that train of thought, one of the OEM motorcycle engineers just informed me that he has been finding that the small oil passages that feed the cam bearings are getting plugged with material off the paper oil filters. It comes back around to the consistency discussion.
The simplest cleaning, and the one I like the best for the average consumer, is brake cleaner or carb cleaner, sprayed first inside out through the screen and then around the outside to wash the debris off. A soft bristle brush (like a toothbrush) can be used to dislodge stubborn debris if needed. If you want to go the extra mile, flush with soap and hot water. If compressed air is available, use it to blow from the inside out and then around the outside. Otherwise air drying works fine.
If the particle is too large to get through the filter cloth, normal cleaning won’t “push” it through. The weave of our stainless steel wires keeps the openings pretty stable. If you believe that some dirt got washed into the inside of the element, just flush it out real well. The element, bypass valve and epoxy grooves are designed to make it as easy as possible to clean the inside of the element (when you look into the element you can see the entire inside of the bypass valve as well).
The other thing to watch for is that we have had a couple of look alike filters show up out there in the reusable arena. We are flattered that they like our product and want to imitate it, but we have tested several of them and they have performed worse than the worst paper filters we have tested. They even use our copyrighted material to promote their product so make sure you get a genuine K&P Engineering manufactured product to ensure the quality. All of our filters have packaging that identify them as a K&P Engineering manufactured product.
I’d just like to note that we think it is great when people want to get more educated on oil filtration. Many people don’t pay much attention to the subject. They look for the cheapest filter to throw on their engine thinking they all perform the same.
I appreciated the candid response and it wasn't overly "sales pitch" and thought it was worth sharing.
I also asked about cleaning the filter and the idea that tossing in a fresh "clean" paper filter eliminates the posibility of reusing a contaminated filter from improper cleaning technique.
This is a portion of the response from two emails:
(I have Dave's permission to post them)
The only way to compare the filter media directly to each other is to run them through the same test at the same time. I haven’t found anybody who could explain to me how you can scientifically use two different beta ratios to compare media, even though it is commonly done. Basically, throwing out a number at some percentage of efficiency just sounds good from a marketing perspective. Actual media performance is much more complicated. And there are plenty of white papers out there on the different theories. On top of it all you’ve got the media’s consistency factor as well as bypass operation and bleed by helping to complicate the subject.
In order to compare the baseline filtration of filter media we use the ASTM test which eliminates percentages, averages, multiple passes, and all the other variables the SAE tests allow you to introduce. From the side by side lab tests we have had done, we meet or exceed the filtration performance of the factory filters. You may or may not want to take our word for it, after all we are a manufacturer and this could all be marketing jargon.
When we run filters through the ASTM test, the paper filters (even the ones with 10 microns on the box) will actually pass particles ranging from 45 to 90 microns. The stainless cloth we use doesn’t pass anything larger than 35 microns (it actually tested at 17 microns). So yes, we meet or exceed the filtration of the factory filters as well as other (aftermarket) replacements.
We feel the real benefits of the filter are in the increased flow of the filter media, reusability, ease of inspection and reduced environmental impacts.
Remember that the stainless steel filter flows many times more than a new paper filter, so even if the ss filter is 50% plugged with debris, it will still flow around twice as much oil as a new factory filter.
It is nice to believe that a new, fresh paper element will give you the best starting point for cleaning your oil. However, think about the cellulose particles that may not be totally attached to the paper mat (either in glued or pressed construction). Not a problem with our ss filter. Think about any dust and dirt that may have gotten into the filter during manufacturing, packaging, shipping, customers fondling the product on the dealers shelf, etc.. At least with ours, you can clean it prior to use to make sure it isn’t introducing any of that material into your engine (like you would with any other critical engine component). To substantiate that train of thought, one of the OEM motorcycle engineers just informed me that he has been finding that the small oil passages that feed the cam bearings are getting plugged with material off the paper oil filters. It comes back around to the consistency discussion.
The simplest cleaning, and the one I like the best for the average consumer, is brake cleaner or carb cleaner, sprayed first inside out through the screen and then around the outside to wash the debris off. A soft bristle brush (like a toothbrush) can be used to dislodge stubborn debris if needed. If you want to go the extra mile, flush with soap and hot water. If compressed air is available, use it to blow from the inside out and then around the outside. Otherwise air drying works fine.
If the particle is too large to get through the filter cloth, normal cleaning won’t “push” it through. The weave of our stainless steel wires keeps the openings pretty stable. If you believe that some dirt got washed into the inside of the element, just flush it out real well. The element, bypass valve and epoxy grooves are designed to make it as easy as possible to clean the inside of the element (when you look into the element you can see the entire inside of the bypass valve as well).
The other thing to watch for is that we have had a couple of look alike filters show up out there in the reusable arena. We are flattered that they like our product and want to imitate it, but we have tested several of them and they have performed worse than the worst paper filters we have tested. They even use our copyrighted material to promote their product so make sure you get a genuine K&P Engineering manufactured product to ensure the quality. All of our filters have packaging that identify them as a K&P Engineering manufactured product.
I’d just like to note that we think it is great when people want to get more educated on oil filtration. Many people don’t pay much attention to the subject. They look for the cheapest filter to throw on their engine thinking they all perform the same.
I appreciated the candid response and it wasn't overly "sales pitch" and thought it was worth sharing.
