KZ650 - WTF is \"air injection system\"?

I finally found my donor 79 KZ650. Got a great price too. 7000 original miles, one owner, sat in a garage. Minor surface rust but if I kept it stock, I could clean it up real easy to a almost new condition. I paid $500 only. When I looked at it, it wouldn't start though. But after looking it over it seemed like it was well taken care of (turned over well, no oil anywhere, the brakes & clutch still felt "new", etc) & the risk of buying a $500 lemon was minimal. All we did was replace plugs, change oil, & clean the points & voila - started right up. We just need to clean the carbs as two are leaking gas & we can get it on the road! The first step is done.

To my question:

I want to do individual carb filter setup so i will remove the airbox. BUT there is another hose going into the box for this "air injection system". So where will this hose go when I remove the airbox? Can I get a mini pod filter for this hose? Or can I remove the hoses completely & just put mini pod filters on top of the openings of the air suction valve on the valve cover itself? In looking at the manual there is also a smaller vacuum hose & vacuum switch valve. Well do I need all this too if I have pods? If so, how do I re-route this? Or do I really even need this "air injection system"? I hope this makes sense. Thanx all.

Here are some links on the subject.
When the airbox is gone, the hose and the contraption it goes to can be removed. You can get rid of the system as long as you plug the ports on the valve cover and all of the vacuum ports involved.

kzrider.com/component/option,com_joomlab...id,2/id,28448/#28448

kzrider.com/forum/viewthread.php?tid=25074

thanx Loud. I posted in that other thread...