K&N Airfilter Question

[dle52]

I replaced the stock air filter on my 2002 400EX with a K&N. I noticed that when I idle and warm up the bike that about 1/4 - 1/2 throttle while sitting still causes power loss and the bike dies. Anyone have a solution? Rejetting? Need help ASAP, am leaving in two weeks for Glamis.

Go up to a 40 or 42 pilot jet and lower your needle clip 1 notch,,which means you'll be raising the needle up..I bet this will fix your problem..after you get that fixed..I'd remove the airbox lid and up your main jet 1 or 2 sizes for even more airflow and power.

[Str8Wicked]

I have this problem also when the bikes cold but when it's warmed I have no problems.... Also I have an open aluminum airbox so that may make a difference. I'm planning to re-jett anyways when I finally get my pipe...

[Doibugu2]

When I bought my K&N filter, I also bought the Jet Kit. With no other mods to my quad I had to move down the main jet from a 146 to a 142. I also switched the needle and moved it a notch. Sounds like your running fat. My airbox lid is also still on.

Once I did the rejetting, I noticed a little increase in throttle response, but when I just had the filter on, I did not notice anything.