I have a 400ex and was thinkin about gettin a K&N power kit. This is gunno sound like a really stupid question but i dont know much bout this stuff so where would the outerwear go? Do u have to have the lid off to have it? Any help would be nice thanks

 

And to add to this stupid question what does the pre filter do?

 

The outerwear is a sleeve made out of a material that resembles parachutematerial.It goes over the K&N filter.They help keep dirt and water from getting to the filter.This is the pre-filter.You can use the airbox lid,the filter setup will be the same size as stock.You can get an airbox cover made from the outwear material also.Work good if you decide not to use the airbox lid.

 

Thanks

 

Is the kit goin to help much or is it not worth even getting.

 

Im not sure what all you get with the kit.If it were me,Id get a UNI or Twin Air filter and check the jetting.Ive ran the KN on my R and (with the outerwear) and still found some grit in the air boot.The foam filters seem to filter better and still flow better than the stock one.Use a good filter oil like FFTor UNI.No Toil makes good stuff too.I dont know how big the gain will be.What pipe you running?To get the biggest gains,you need to do mods in pairs.More air/fuel in doesnt help much if the exhaust is restricted.The filter/rejet is a good one to start with tho.