Here's the bike 09 klx250s
Fmf powercore 4 stock header
Stock snorkel (kdx snorkel on order)
Altitude 500ft

Installing the dyno jet kit and kouba screw
I first tried the 120 jet. I could get the idle to drop off when I turned the kouba in not when I turned it out almost turned it out to 4 turns.

Now I just installed the 128 and it won't idle unless I turn the kouba out 3 1/2 turns I tried removing the air box lid no luck.

Kouba instructions say not turn out more then 2 1/2 turns or it will vibrate out.

What am I doing wrong

 

Try the stock mixture screw. Setup per the DJ instrutions. The taper on the Kouba screw may not be close enough to the stock piece. Good luck.

 

I'm confused the kouba screws don't work with the klx250s

 

Compare the two, are they the same on the business end? We already know the stock screw works.

 

The D/J kit doesn't effect the idle/pilot circuit, so any problem making adjustments will be because of the Kouba screw. Make sure that you have installed the new needle properly per the instructions and that all of the jets are clear of any debris. If you still have issues I would try the stock air screw and see what happens.

 

I screwed up big time I went check to see if the diaphragm was seated properly once I opened it up it was oversized. It won't fit back into the grooves.

 

I let it sit out over night and shrunk back to the right size.

 

Thanks for everyone's help. I ended up going with the 128 jet, the stock screw 3 turns out and removed the snorkel. Its idling great and awesome when I took it for a spin.

 

Many of us run the Kouba screw without issue but if it is dammaged in any way it could be an issue, even seating it too firmly can mess it up.

 

After taking the carb out for the 4th time, I wanted to put it back with confidence that something would happen. Im not very mechanically savy so I stuck with the majority's ruling on this thread and the tech at Dynojet and went with the stock screw. If I have any altitude issues with the carb then I will try messing with the kouba screw again. Its mostly likely something I did not the kouba. Thanks for the help. I couldn't have done it with out the KLX forum.