Air Filter Foam PPI?

[bluechrome]

Hi
I am redoing the OEM filters on my '79 XS400 and need to replace the foam around the element. Does any one know what the rating of this foam should be?
The suppliers say it could be anything from 10 to 80 PPI where type 10 has large cells and is very open whereas PPI 80 has small cells, is more dense and has a lower air flow.

Your help is appreciated.
Thanks

 

[xschris]

Not sure about the ppi but people that have re-covered the oem ones have used the green colored foam used on lawn mower air filters.

 

[norrie]

Not sure about the ppi but people that have re-covered the oem ones have used the green colored foam used on lawn mower air filters.

And then do you need to stray some kind of lubricant on the foam? I've just decided to drop the pods and go back to stock.

 

[xschris]

I would just get a set of oem filters. There are lost of after market ones that are just as good as the originals. Ebay has a lot of them and I have seen them for under $20 each.

 

[Tate]

I bought a 9x21 sheet of No Toil air filter from a local bike shop. It can make x16 strips , which is plenty. Under $20 too!

 

[xschris]

Keep in mind that what you are doing will NOT work as well the oem filter did and the bike may need tuning. The stock filters came dry and without oil.

 

[Tate]

Hmm. That does make sense, however, this foam is oil free. I haven't used them yet as my bikes are in a rebuilding phase.
Is the oil foam more of the concern or is it the density or make up of the filter itself?
Thanks
I did keep the receipt!

 

[xschris]

The type of foam used in the oem filters is different. There is also a second layer almost like a hair cover over it.

 

[xschris]

The foam is different and there is also a second layer that looks like a hair over it.

 

[norrie]

Thanks! I have another question. Looking at the parts in my box, I have the filter boxes, brackets and tubes that run back to the carbs. On those tubes, there's an inlet/outlet in the middle. What needs to happen there? Something obviously plugs in there but I don't know what.

 

[16VGTIDave]

Crankcase vent.

 

[norrie]

Crankcase vent.

Thanks! So that would quite possibly be the tube that currently has this little pod filter on it?

 

[BBS360]

That'd be the one. Normally the crankcase vapors get sucked into the engine and burn up.

 

[norrie]

That'd be the one. Normally the crankcase vapors get sucked into the engine and burn up.

Awesome! Thank you.