its been so long since i jetted it i dont really remeber, but i know i didnt get a pilot jet replacement only a main jet. whats up with that? where is the air screw is in in the inside of the carb?

 

The fuel screw (air screws are only on 2 strokes, I think) is on the outside of the carb more toward the engine.

 

jimmalips....your running dynajet mains and the others are talking about mikuni mains

 

Yep, the fuel screw is at the bottom of the carb and is covered with a small brass cap. The cap has a very small hole in it's center. You have to drill the hole to 1/8" ( don't drill too deep, you will destroy the screw!) and thread in a self tapping screw. Pull the cap out by grapping the screw you inserted with pliers and you will see the fuel screw. Adjust to your liking. Mine is set at 3.5 turns out with 165 DJ main and needle clip in the 3rd position. That's with a Big Gun full exhaust and a K+N filter with outerwear cover, no lid on the airbox.

 

Quick note: The brass cap is only on some carburetors like those to be sold in California. The rest of us are lucky enough not to have it.

 

Hmmm, that's strange as I bought mine new in Jersey ???

 

What is the air screw set as stock on the kfx400? 2 turns out ?

 

According to the service manual, it's pre-set at 2 1/4 turns out. Mine was only at 1 turn when I removed the brass cap, but I might have tightened it a bit when I was threading in the screw to remove the cap [img]i/expressions/face-icon-small-disgusted.gif[/img] .

 

Hmm that makes me wonder were mine is set now.

 

Yeah, I think it's worth a look. There's no way I turned mine in 1 1/4 turns when I threaded in the screw to remove the cap. I checked the slot on it and it was clean, no marks. Me thinks they are setting them more for emissions rather than performance [img]i/expressions/face-icon-small-happy.gif[/img] . Simple fix [img]i/expressions/face-icon-small-wink.gif[/img] .