I have put a K&N filter in my bike and have adjusted the screw and the white spacer is gone.  I took off the airbox cover and the sound is much better from the bike.

However, I notice at full throttle when each gear approaches close to redline, the bike kind of hesitates like it is not getting enough something.

Should I not have removed the cover or do I need to further adjust the screw?  Please note the bike has the stock jetting still on it.  The jetting has never been a problem yet.

Also, I was wondering about this desnorkel stuff?  What is the snorkel and where can you find it on the bike?  What do you do with it to perform this mod when you find it and what does it do to the bike?
Thanks,

Purpose of the snorkel is to direct the leaf-blower like air blast straight at the bottom of the air box, letting it fragment there, swirl around then go through the filter.

De-snorkling puts the air blast aimed directly right at the very top edge of your air filter.  This puts a physical wind load on that section of the filter, causing rapid dirt fill and premature "filtration failure" of that area of your K&N media.

Removing the air filter door allows air to gracefully enter from all sides, removing most of the wind tunnel effect of the desnorkled closed air box.  It allows minimum resistance to maximum air flow and provides the best even use of your filter media.

BUT IT IS NOISY.  Noisier, anyway.