So for the people that have a K&N air filter with no other modifications, does it make a difference with power and fuel mileage? I have a stock 2000 Honda CBR600F4. I am going to install a slip-on Two Brothers exhaust. So I wanted to get some opinions if it is worth getting a K&N air filter. I got one for my old 1995 Honda Civic back in the days and it didn't seem to make a difference with power, but I did notice with fuel mileage.

 

K&N products will put your mind at ease about their reliability if nothing else. They have never let me down and i use both air and oil filters in cars and bikes. They do recommend getting a retune for an aftermarket exhaust/air filter but its not ness, unless you have a power commander then you can download that tune. The air filter has a lifetime guarantee and for 60 bucks worth every penny. The air flows better but the HP gains are very small, but if you put an induction kit on a car and take out the air box, you can really hear and feel the HP gains. Oil filters just trap more particles and flow better so they are more efficient for the engine

 

Pretty much sums it up quite nicely...

On my F4 a slip on and a k&n yielded a bit more pep up top.

 

Id say if anything a slip-on and K&N gave more mid-range to my f4 - i guess it may depend on the bike and the slip-on.

 

I've always had good service n nice gains from K&N.