How can a BMC Race air filter make such a huge performance difference?

[Liltroy]

Ok, my bike already had a BMC filter in it when I bought it. So how do I tell if its the Race filter or the other BMC. I cant find any reference numbers on it....Just the BMC logo.

 

[tinmann840]

The race filter will have a yellow line around the middle of the filter. Does anyone run a BMC or KN filter without the oil?

 

[2busa]

I installed a K&N like a BMC and I did feel a slight change. Nothing to write home about. It just change the air restriction is all it did is my guess. I'll stay tuned not say a word or I might give it away and pay hell for it.