Sticky throttle after jet kit install
 

Jet installed jet kit in myh 2009 KLX250s- runs great but at half throttle or above the throttle sticks a little-slow to return automatically to idle with hand off throttle. Its somewhere in the cable- carb end is ok. Did I kink the cable somehow or did disconnecting the cable from the carb somehow screw something up at the grip??

try loosing up the nuts that hold the cable's to the carb thats where i would start....good luck....by the way welcome to kf

check that the throttle cables are not kinked or pressed or on an awaked angel. under the tank it is very easy to kink.

I got it fixed- somehow moving the cable around to remove the carb misaligned it at the grip. Took the controls apart, aligned the cable- good to go!

09 DJ kit
 

I just installed the 2009 DJ kit also, and had a problem.
The slide spring provided in the kit is too soft, and would not let the slide return to rest after a hard acceleration. There is something hanging up on the slide, and the stock spring is strong enough to overcome what ever is hanging it up. (maybe it is too new and needs to wear into place) So i put the stock spring back in and drilled the slide to 7/64ths, like the older kits. Seems to be good now, but has a little hesitation from off idle. I will drill the slide a little bigger and see if more vacuum to the diaphragm will simulate the lighter spring. I'll let you all know what size works the best. If anyone has already fooled with this, let me know so i don't waste time and effort.
Thanks,
Gary

The cables are sensitive to routing, even if you dont remove the cable entirely. Even with both ends of the cable hooked up & routed as they were from the factory I can shift my cables up, down, in, & out of where they kind of rub/pass through the frame & wiring & have it affect the throttle return when turning the bars lock to lock. I just find where it works the best & they pretty much stay there. Mine will always will snap back with the bars are straight ahead though.

All the R&D has been done before. The optimum size for the vent is 7/64", any larger can result in resonance and hover of the slide.:D

+1, don't drill it any bigger or you can get an effect that acts like lean surge at steady low load cruise that can't be jetted out. Even 7/64' can be too much on some bikes.

Hmmmmm , even with the bigger bore?????
I guess the bigger bore would actually create more vacuum.