TOPIC:

Strange question, but can anybody tell me how thick (MM? Inches??) the foam air cleaner pad is that goes inside the KZ400 air box?  That would be #4 in the attachment...
 

Oh, I guess you're replacing just the filter element then. I did that with a Z200. What I ended up doing was buying the new one, which was thinner and made up of 2 foam densities, and sticking that on. Because I figured it's better to have a new clean thin filter element than an original dirty one. Anyway, the foam on the Z200 one was quite thick - about 10mm IIRC.

The fuzzy stuff and foam is 11.5mm.

Thanks guys; actually, I'm surprised it's that thick. I don't have that air cleaner insert so I made my own. Whattya think...?  This is just the prototype, I want to make some adjustments to the final construction. It's measured to fit into the air box like a glove, but I didn't know the thickness of the element filter, I was surprised to see that it's that thick. I was wondering about air flow, and how restrictive it is... 

 
 

Filter holder looks good. As to the air flow, that will depend entirely on the density of tha material used. I have never seen any measurement of the factory foam. I think many folks buy a sheet of foam material from Uni, and cut to fit. Flow should be fine, maybe a little more than stock.

I bought a sheet of Uni 5/8" green foam to make a filter for my 84' VF 700S. It's cheap and is enough to make 4 Sabre filters. Factory was 1/2" thick but the 5/8" is working just fine.

Filter mats for kitchen extractor hoods are dirty cheap!