Foam air filter test
- Thread starter pda1122
- Start date
UNI the worst ? I’ve been doing it wrong all this time ?
Starting to see why Twin Air "recommends the use of a pre filter" for dusty conditions and sand. Lots of sand riding down here. Might go with Moose or NoToil on the next filter.
This is just one guy's test but it seems well done. Frankly, I am not too shocked by the results he got. No-toil has always been a good filter, I will continue using them. Moose has always had good stuff with good value behind it, good for them.
Twin air has always had a good reputation and I am a little surprised by the results. As for UNI, I always thought the cell structure of the UNI foam looked too open/loose and this test seems to confirm my suspicions.
Twin air has always had a good reputation and I am a little surprised by the results. As for UNI, I always thought the cell structure of the UNI foam looked too open/loose and this test seems to confirm my suspicions.
Maybe I just don't get it, but this doesn't make much sense to me.
This test is about light refraction and light filtering. Dirt and dust particles are not anywhere in the realm of the magnitude of photons, and they have completely different natures. Dust particles do not refract through filter media in the way light does and don't pass through an oil film like light will.
This would be like testing a colander by pouring water into it and concluding that it would not drain pasta properly because water goes right through it.
This test is about light refraction and light filtering. Dirt and dust particles are not anywhere in the realm of the magnitude of photons, and they have completely different natures. Dust particles do not refract through filter media in the way light does and don't pass through an oil film like light will.
This would be like testing a colander by pouring water into it and concluding that it would not drain pasta properly because water goes right through it.
Originally Posted By: MotoTribologist
Maybe I just don't get it, but this doesn't make much sense to me.
This test is about light refraction and light filtering. Dirt and dust particles are not anywhere in the realm of the magnitude of photons, and they have completely different natures. Dust particles do not refract through filter media in the way light does and don't pass through an oil film like light will.
This would be like testing a colander by pouring water into it and concluding that it would not drain pasta properly because water goes right through it.
So you didn't read the whole thing.
Maybe I just don't get it, but this doesn't make much sense to me.
This test is about light refraction and light filtering. Dirt and dust particles are not anywhere in the realm of the magnitude of photons, and they have completely different natures. Dust particles do not refract through filter media in the way light does and don't pass through an oil film like light will.
This would be like testing a colander by pouring water into it and concluding that it would not drain pasta properly because water goes right through it.
So you didn't read the whole thing.
Originally Posted By: rooflessVW
Originally Posted By: MotoTribologist
Maybe I just don't get it, but this doesn't make much sense to me.
This test is about light refraction and light filtering. Dirt and dust particles are not anywhere in the realm of the magnitude of photons, and they have completely different natures. Dust particles do not refract through filter media in the way light does and don't pass through an oil film like light will.
This would be like testing a colander by pouring water into it and concluding that it would not drain pasta properly because water goes right through it.
So you didn't read the whole thing.
I thought I did. What did I miss?
Originally Posted By: MotoTribologist
Maybe I just don't get it, but this doesn't make much sense to me.
This test is about light refraction and light filtering. Dirt and dust particles are not anywhere in the realm of the magnitude of photons, and they have completely different natures. Dust particles do not refract through filter media in the way light does and don't pass through an oil film like light will.
This would be like testing a colander by pouring water into it and concluding that it would not drain pasta properly because water goes right through it.
So you didn't read the whole thing.
I thought I did. What did I miss?
Originally Posted By: bulwnkl
That the amount of dust that got through the filter and onto the test piece correlated well with how much light one can see directly through the filter.
Correlation Does Not Imply Causation
I could make a foam filter with one inch pores that lets zero light through. I suspect it would quite poorly at filtering dust though.
I could also make a "filter" that let nearly 100% of light through that I could guarantee would stop not only 100% of dust but even the air molecules too.
So please explain how dust and light behave similarly.
That the amount of dust that got through the filter and onto the test piece correlated well with how much light one can see directly through the filter.
Correlation Does Not Imply Causation
I could make a foam filter with one inch pores that lets zero light through. I suspect it would quite poorly at filtering dust though.
I could also make a "filter" that let nearly 100% of light through that I could guarantee would stop not only 100% of dust but even the air molecules too.
So please explain how dust and light behave similarly.
And besides my above comment, the test method to used to determine the amount of dust passing through is far from quantitative. Yes I realize the tester did not imply they were and only listed observations, but it is highly flawed to make conclusions based on that, in my opinion.
A much better method would have used a second filter with massive efficiency numbers and comparing before and after weights for dust passed through the initial filter.
A much better method would have used a second filter with massive efficiency numbers and comparing before and after weights for dust passed through the initial filter.
No one claimed a causal link, and that and your ability to get someone to manufacture foam for you that is intentionally not good at air filtration is irrelevant.
I understand a desire for improved scientific rigor. That would have been nice. Perhaps you'll do such a test and post the results. Shall we all hold our breath waiting for that?
Until better info is available, the positive correlation between the two observations is very interesting.
I understand a desire for improved scientific rigor. That would have been nice. Perhaps you'll do such a test and post the results. Shall we all hold our breath waiting for that?
Until better info is available, the positive correlation between the two observations is very interesting.
Originally Posted By: bulwnkl
I understand a desire for improved scientific rigor. That would have been nice. Perhaps you'll do such a test and post the results. Shall we all hold our breath waiting for that?
No need to hold your breath, it was done years ago and has been publicly available for years. It is a comparison of filter oils though, not filters themselves. If you are aware of who I am, you know why I won't be posting a link to it, but it really is not difficult to find once you figure that out.
I understand a desire for improved scientific rigor. That would have been nice. Perhaps you'll do such a test and post the results. Shall we all hold our breath waiting for that?
No need to hold your breath, it was done years ago and has been publicly available for years. It is a comparison of filter oils though, not filters themselves. If you are aware of who I am, you know why I won't be posting a link to it, but it really is not difficult to find once you figure that out.
The link provided is dead. The cynic in me says possibly Uni Filter contacted haroldbawlzangya.com and paid him to take his web site down to kill the bad publicity.
It's on the Wayback Machine...
https://web.archive.org/web/20201029084319/https://haroldbawlzangya.com/air-filter-test/
Thanks DaveInIreland.
Wayback Machine? Never heard of it. Did a search of Wayback Machine and entered the web site URL from post #1 and all i got was
Could not find the archived filter test. Am i doing something wrong?
I would appreciate an archive link if possible.
TIA
This is the expanded link...
https://web.archive.org/web/20201029084319/https://haroldbawlzangya.com/air-filter-test/
Click on "Air filter test" and it will open the archive.org page.
I tried to show the long link, but this site won't let me.
https://web.archive.org/web/20201029084319/https://haroldbawlzangya.com/air-filter-test/
Click on "Air filter test" and it will open the archive.org page.
I tried to show the long link, but this site won't let me.
Thank you very much DaveInIreland for the link.
What a full on test/review. This guy is really keen but in a good way. We would get on well together with his apparent OCD for experimentation & detail.
I had a skim over the link contents and will take a more detailed look later when time permits.
Maybe the UniFilter will NOT be going back into my bikes air box.