air filter

i ran the k&n in my blaster. they are a bit pricy, but they are life time filters. i would recomend if you ride alot or sandy or dusty areas you get a outer wears pre filter for it too.

if you want a good filter, but your gonna have to replace them every year or 2, get a UNI.
 
I duno if K&N has ones that drop into the stock box...do they? The only K&Ns I've seen on quads replaced the whole airbo and were open to mud and water clogging them up. A buddy ran one for a while back in the day, used to get clogged up with debris and such...so he would use pantyhose (this was before filter wears was around..oratleast before we knew about it).

I recommend getting a few UNI or TwinAir, or similar name brand foam filters. That way you can keep a clean one ready and switch out when your dirty....and not procrastinate changing it because you want to ride and don't want to clean the filter first!