Not sure about the stateside 07 version, but my decel popping went away when I removed all of the AIS hoses and capped off the ports on my 01 D-Tracker. You might try that. Aynone done this on 07?

 

Popping++. Bikes still lean. Go the needle 4th clip from top (it's only a #128 main, factory is #132 here for the 250). I found the #40 pilot to be too rich for my 250. I't worked OK but the bike would idle inconsistently and at times stall when I stopped at turn signals. How does yours run on/just off idle? I got it just right when I went down to the #38 pilot. Great pick up off idle and idles without fault, steady as. Try the needle first (10 minute, NO carb out job.) I really think that with the 300 kit you should at least be running a #132 main jet. My .02.
I love the Two Brothers pipe. Loud. Ear plugs when I ride though.

 

Thought I'd bump this thread instead of starting a new one - about myself (and my bike )

I'm 22 years old, live in Fort Worth, Texas and I work in Enterprise, Utah. I got my motorcycle license a year ago and just now got my first bike, a new 2009 klx250s. I chose it 'cos it was cheaper, lower, and got better mileage than the 650 - have about 1200 miles on it so far, and I must admit, I am quite happy. I'll probably lurk for awhile reading old threads and stuff, but in the future when I have more frequent access to a computer, I'll be posting a lot of pictures probably!

 

Welcome.

 

Welcome..."Doga!"

 

Way to go Doga!! Plenty of info to go back and read on here.

 

This thread is old, I wonder where he is?