je2000,
09KLXowner has given you valid advice. I did the "usual" fuel system mods. and had NEARLY the same results as you. I had normal accelleration up to 1/4 throttle (pilot circuit) then NO acceleration from there on. I thought that I'd been very careful but now believe that either I did not have the diaphram properly seated (unlikely!) OR there was a speck of dirt between the jet needle and the needle jet (most likely), causing the needle to "stick". All I did was to remove the carb and look at the jet needle ( for proper operation) and then reassemble the carb. I think that the act of lifting the needle dislodged a speck of dust and allowed the carb to operate normally when I re-installed it onto the bike. It ran VERY well afterward. The clearance between the jet needle and needle jet is very close and only vacuum is being used (against a spring) to lift the jet needle up out of the needle jet. So. . . . when you disassemble the carb again, make certain that the needle is free to move. In case you don't already know, this circuit is your 1/4 to 3/4 throttle circuit. Understanding the various fuel circuits will help you solve fuel problems indicated by throttle position.
Forgot to mention. . . . the K118 main jet IS the stock jetting from the factory.

 

original post- used with 1000 or so miles.

 

i just installed a 40 pilot jet, nt1c needle(3rd clip), 135 keihen main jet and adjusted the a/f screw to 3 turns out and my bike runs stronger than ever! i waisted my money on a dj kit!

 

Hey guys, thanks for all your input. I'm going to open the top up and dismantle the diaphragm slide and needle and see if anything is wrong. I think that it is just not lifting properly Then I'll put it all back and see if I just didn't have something seated correctly.

I also had two left over large washers with the muzzy. They call them spacers. The instructions never say what to do with them. I'll call em up and see what they say.

One last request....I can't seem to find that chart showing the differences between all the different main jet sizes and manufacturers...

Dynojet 128 isn't the same as Kein 128, etc. etc.

 

This might have the answer for you:

http://faq.ninja250.org/wiki/Dynojet...zes_conversion

However, be sure and read the "A note from Dynojet":

So he's saying that you really can't just go by the diameter of the hole. There are other factors that contribute and there is not a one to one match-up.

 

ha.... laziness kicking in again....lol

 

This may be your problem. Fitting the full Muzzy and Twin Air filter will increase the airflow through the engine considerably. The 09 DJ needle, I believe, isn't designed with these upgrades in mind (more just pep up the stock set up,) the KLX300 DJ kit is. Check the different taper on the needles. I suspect as others do, you are running lean. If you still have the DJ #128 main jet in place I would raise the needle at least another position, even two. (lower the clip.)

What does your needle look like. Left or right?

 

Yup, like I said from the beginning. Your running lean.

 

The instructions from the kit mention using a K&N filter specifically, which has more air flow than the TwinAir. In addition to suggesting the K&N they say either stage can be used with an aftermarket exhaust. So I'm not sure where you're getting that idea from that it is not designed for anything but a stock filter and exhaust. Please no 300 kit vs 250 kit, we've done that already.

After checking the top of the carb to make sure everything is seated properly per the Dynojet instructions I'll give Dynojet and Muzzy a call. It's highly possible something just isn't installed correctly.

 

You could very well be right. I'm just thinking the diaphragm is an easy thing to check and can also result in similar behavior. I'm not saying I'm sure it is the diaphragm, just a good place to start, IMO. I would at least rule it out first.