This summer when I wascleaning my K&N filter, I removed the air silencers bolted to the lid. I figured those plastic tubes tookup alot of air space within the airbox. By removing these silencers to free up room inside the airbox, would this modification have helped the bike breathe more air? It runs fine without these tubes except that you can hear more noise comming from the airbox which is nota big problem. I took a ride around the block without the lid to see if there was any performance increase but to my suprise, it made the engine bog whenever it was under load. The reason I ask is because for the Dynojet Stage 2, it recommends a modified stock airbox. I wasn't sure if removing the silencers was beneifical in considering the airbox modified or if this setup actually flows more air?

Right now I am running the needles clips at 4th position as per the stage 2 instructions except I am running Kehin 117.5 mainjets which is the same as DJ112 mainjets for the Dynojet scale. The stage 2 comes with DJ120 and 124s. So basically I am running a stage 1-1/2 kit and I'm not sure if I need to come back down to the stage 1 or leave it since the airbox is "modified enough"?

 

I don't run them on my bike,didn't realy make a noticable difference

 

I am thinking about picking up a used airbox lid to drill multiple holes in the top for increased airflow. Has anybody ever tried this on a CBR hurricane? My thought is if it doesn't, at least I still have the old lid.

 

Yup, many have done the airbox holes, but you have to block the front of the tank/airboxjunction to keep too much air from getting in.
I run without the silencer as well and did notice a little of bogging until we retuned the carbs. Every time you do any airflow upgrades you need to rejet or retune your carbs.

 

To me, it seems as if you have to block the incoming air holes in order to make it work, than the original setup seems like it would flow more air without drilling holes?

 

Not the incoming air holes, just between the top of the tank and the airbox lid. So you drill the holes into the airbox lid, then use some camper tape or some other airdam around the front of the airbox/bottom of gas tank. Basically keeps too much air from being rammed in there at speed. By blocking the front it still can flow in from the sides and rear. Way more than stock, but less than a ram air setup. You have to keep the front snorkels hooked up as well.