Hello.

I just installed the air filter, and now I will install the jet kit sometime this week. What do you suggest for the main jet size? My 400EX is stock, exept for the brand new K&N air filter.

I am wondering what jet size should I use with, and without the airbox lid. I am interesting in trying both to see which option is the best.

Thanks

 

Am I the only one having this mod combination?

 

I have the dyno-jet kit. the directions should tell you what size to run for what combo. I use a dyno 170 in mine, but I have an aftermarket pipe and no lid. I know you will like the kit, it does not make you any faster, just better response.

 

Sweetcorn,
Right around the corner here in Greenville,
Anyway, I just installed the wb s bend slip on my 400ex and got the k&n stage 2 jet kit.
Should I start with a 160 main, and 42 pilot, and needle up on notch?
Greatone

 

Been trying to get the jetting right with mine as well. I bought the only jets in town for the khein carb a 41 pilot and 158 main jet. Runs rich at idle to about 1/4 throttle, loads up at sustained high rpm. So I bought the k&N power kit, unfortunatly it only comes with main jets! I put in the 170 like they recommend and it won't idle on its own, and is really rich throughout. I jetted down to 160, which is what is recommended by my exaust mfgr. Still no idle, next step down in the kit is a 155. I will have to swap the pilot back to stock, I think that is where the problem is. The mixture screw that the kit says to adjust does nothing, unlike the on a car. Also when I say it won't idle, I have the screw all the way in, and there is nothing wrong with the linkage. I live at 650 asl, but I believe the air is thinner up here as we have a lower tree line than the lower 48, and my timeslips at the dragstrip prove it.

What do ya'll recommend?

 

did they give a needle too? the mixing does make a diference on my 400, when I first installed the kit it would cough a litle when I let of the gas, so I turned it richer and it fixed the cough, but It drips gas out the carb drain tube, but not alot, I thought about changing the pilot to see if that would help, but never got around to it.

 

ah I been to greenvile before, do you ever go to silver? we will be there this weekend and july 15 weekend(weather permitting) looking forward to it, been a long winter. I installed my dyno kit to the directions specs, 170main, 3rd notch, and mix screw 3 turns out. I got a pipe, k&n, and no lid below. It works great so far, fires right up, don't even need the choke most the time. to only problem I have had it gas seeping out the drain tube, I thought about changing the pilot or ajusting to floats but never got to it. to busy riding, let me know how it goes

 

Dripping fuel? check your float level, it could be too high also causing a "too rich" mixture. The float level has to be at or at least very near factory specs or you'll be searching for the right combo having to "wing it" , the kits are based on factory fuel levels.
Use the factory pilot jet too, it sounds like you'll need to be starting from scratch, just like the jet kits are designed to be set up with. Unless you're working with a highly modified engine the "lower engine speeds/air fuel mixture" won't need a bunch of tweeking.

Lou......pepprdog

"Tippmann Pnuematics" (paintball) forum Administrator......"http://www.tippmann.com/forum/"

 

Sweetcorn,

I did the same just followed the directions with the 170 jet and the clip on the 3rd notch it works great no leaking.

 

Also can you tell me wear you got the 16 tooth spocket?