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Sub air filter made out of foam?

HondaGoro

Member
Joined
May 11, 2025
Messages
5
I'm honestly kinda bothered by this.. Found a $3 filter online but the shipping fees are just outrageous. Its frustrating for something so cheap!! So I'm thinking maybe I could just use some foam to make my own filter instead. Anyone know if that might work or am I overcomplicating things?
 
I feel you, shipping on cheap parts is the worst. You can make a foam filter, just be sure it's open-cell foam like UNI uses. Avoid household stuff, it'll restrict airflow or break down. Oil it properly, get a snug fit, and you're good. I've done it in a pinch and it worked fine.
 
Yeah totally agree with you.. Good tip on the open cell foam, proper oiling and fit make a big difference. By the way, how long did your DIY filter hold up before needing replacement?
 
I feel you, shipping on cheap parts is the worst. You can make a foam filter, just be sure it's open-cell foam like UNI uses. Avoid household stuff, it'll restrict airflow or break down. Oil it properly, get a snug fit, and you're good. I've done it in a pinch and it worked fine.
I agree with this one. Making your own filter with foam could work depending on what its for, it's a bit of a gamble if the engine needs proper airflow or filtration. Maybe check local small engine shops or even garden centers, they sometimes have generic filter material you can cut to size, and you might avoid the hassle altogether.
 
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