3D printed oem air box lids...
Have you run any of these on your bike yet? If so did it require you to lean the main jet?
The reason I ask was......Years ago I had a customer that modified his stock lid similar to what you had pictured on a 50 hp plus 250. It added enough restriction that it required the main jet to be leaned a couple of sizes. I did not dyno it but I would estimate it lost about 5% to 6% due to the 5% to 6% reduction in fuel flow it took to get it to not rich miss fire at wide open throttle.