X-6 and k&n on stock engine

[Florida400EX]

Hey, I was interested in picking up some more power on my 400ex. Currently the motor is stock, and I ride MX and would like to have a much bigger mid-top punch. I found a Curtis Sparks X-6 pipe and a k&n filter. What kind of gains should I expect? Also, what should my jetting be? I live in south florida, so pretty much at sea leval, with no air box lid.

Thanks!

[hondarider2006]

for the jetting, start at a 158-160 mj, and install a 42 pilot and go about 2 1/2 turns out on the air mixture screw. If you want, remove your choke for a little more throttle response;)

[Quadzilla]

You will lose some low end and lower mid-range and gain upper mid-range and top-end. You will be surprise by how much of each you will lose/gain. It's like Sparks steals a few ponies from the low and moves it to the top. Good for MX, not so good for trail...

[quadkrazy400ex]

you will definitely notice the gains over stock... i have yoshimura rs3 complete with a k&n and i run a 165 main i live in kansas

[04'400ex'er]

Originally posted by Quadzilla
You will lose some low end and lower mid-range and gain upper mid-range and top-end. You will be surprise by how much of each you will lose/gain. It's like Sparks steals a few ponies from the low and moves it to the top. Good for MX, not so good for trail... I knew the X6 has killer mid to top, but I have never herd of a loss of bottom? :huh

[Giz400ex]

Originally posted by 04'400ex'er
I knew the X6 has killer mid to top, but I have never herd of a loss of bottom? :huh Yeah I lost huge low end with the x-6 but wouldn't it be better with the x-4?:huh Isn't the x-6 somewhat designed for a built motor?:huh

[the-ex-files]

I recently did the X-6, and Uni filter. Make sure to be properly jetted too. On my bike I didn't notice much of a low-end loss, but maybe it's just me. I did like what it did for the top end though!:D

[cals400ex]

my buddies x-4 makes more power than my x-6 on our 406 motors. however, i am wondering if some of it is because his is ceramic coated and mine isn't. i just had my stainless steel pipe coated and i am anxious to see how it runs now. it probably won't be back together for a few weeks because i am still waiting for all my other parts.