Is it worth the money??? Any noticeable gains from it??? If so, what brands are recommended?

 

I have a Pingry airbox. I changed that and my pilot jets (to 25s) at the same time and I am running MUCH faster than last year. It is like a whole different machine. If you are using a pro-flow foam filter (don't have any knowledge of the K+N) with the stock airbox, you will notice that there is not much room around the edges for the air to get into the sides and bottom of the filter. After about 2 inches from the front, the stock airbox squeezes in about 5/8 inch on each side. The pingry does not. There is ALOT more room for the air to enter the filter, and hence the engine. More air = more fuel = more power. I surely recommend the pingry airbox for dry conditions. But there is one drawback -

With the stock airbox and an outerwears water resistant cover I had no problem keeping the filter dry during wet rides. But with my first WET ride out with the Pingry box with an outerwears cover, the really wet and sloppy (snow is melting) trail drenched my filter. At times it wouldn't even rev past half throttle because the filter got so wet. To fix the problem I just shifted up a gear from 3rd to 4th, dropping the RPMs and it ran OK. When I drove 1 hr north where the snow was not melted, I had no problem and it ran perfect. By the way, I was running 2 outerwears water resistant covers - one on the airbox and one on the filter itself.

Overall my evaluation is that I highly recommend the Pingry airbox for anyone that is looking for maximum airflow, and consequently, maximum HP.

RR1

 

I too have a Pingry and I love it!!!!!! I am running the K&N filter with Outerwear and it works awesome!! I don't have any experience with wet weather riding other than riding in a couple of mild thunderstorms, so you might want to be careful about riding in water or mud with an open airbox. Good Luck with your choice!!!!!

 

I am running a graydon airbox that uses a 250r filter. I love it and highly recommend it.