400EX w/ FMF Pipe - Jetting - Any Ideas

[Rickster400EX]

I have a 2004 400EX with FMF Titanium 4 slip on, will be adding k&n air filter & will run with lid off, 11 feet above sea level (south florida), avg temp 84 degrees F......any ideas for jetting?

Many thanks,

Rick

[2001-400ex'er]

Try starting around a 155 keinin ( however you spell it) and work from there.

[Chanman420q]

i run the PC4, which is the same as urs just not as loud, an i run a uni with no lid. my jetting is 155 with a 40pj and the needle in stock position, use a 42 pilot tho, or itl be a pain to keep it idling.

[crandles]

Get a dyno jet kit. Follow directions and you will be set. I removed the choke on my stock carb and put a 42 pilot. It is dead on.

[Rickster400EX]

Thanks guys for all of your help.... will be tearing it up this weekend!

[Florida400EX]

Where in South Florida are you? You ride track or trails?