Air filter mods?

I took out my air filter to clean it (3800 miles and it really didn't look too dirty) and I was surprised how thick the mesh is on the internal cage. Anyone experimented with cutting down the spark arrestor mesh to increase flow? Also, if applicable what aftermarket filter have you changed to? What oil do you use?

That steel wire mesh on the air filter cage is an anti-backfire screen.
In the off-chance your bike backfires through the throttle body, that mesh knocks down the flame so your air filter won't catch fire.
All 4-stroke bikes come with this.

Some guys cut it out (usually on off-road bikes), but I'd leave it there.
If you really want to eliminate it, No Toil makes a Hi-Flow air filter kit that comes with a new air filter and plastic cage without a screen.
The catch is that the new foam filter is treated with flameproof stuff.

The thing that doesn't thrill me about No Toil is the oil - it comes off too easily in my opinion, just as you'd expect with an oil that cleans with plain ol' soap and water, which is their whole marketing angle:
Never mind whether or not it's a better oil for stopping dirt.
It's the cleans-up-easily-because-we-know-you-hate-to-service-your-air-filter pitch they're going with.

Very similar to the chain wax chain lubes when they came out 20 years ago:
Doesn't matter if they're as good as the older chain lubes at actually lubricating anything because when you use too much of it and it flings off onto your rear wheel, you can't see it!!! :)
That was the basis of their original sales pitch.

For air filter oil, I will always use a good, ol'-fashioned petrolium oil, and my choice has always been Maxima FFT.
Goes on watery-thin, and then becomes mega-sticky.
You need a petrolium-based solvent to clean it off, just like God intended it to be. ;)

I've used both the stock air filter and a Twin Air filter.
No performance difference, although the Twin Air filter fit the metal cage a bit more snugly and securely.
Either one works.

I knew it was officially an "anti backfire" screen, I just couldn't think of the proper terminology late last night after a full day of cleaning the bike. I've seen the Notoil kit, like you not a fan of their oil. I also use FFT. I was wondering if cutting the screen would flow more air? It may be a moot point, if the valves/head will not flow more than the airbox can deliver. It's been so long since I messed with heads (old Harley Evo days), flowbench sold years ago. I'm not too worked up about the negative aspects of cutting the screen; when was the last time you heard of a backfire induced airbox fire? I suppose I could make a temporary cage from coat hangers and/or welding rod and do some testing. I'm all about "free" horsepower.

There's nothing to really be gained there
Always remember you have about 44mm throttle body and some of that it taken up with a throttle plate
Having 5000mm of non restrictive air filter is meaningless
It's like having a 4 ft diameter intake on a 3/4 inch garden hose

Kinda what I figured...