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The new Injectors: Initially, the kit came with 80g/min injectors, and Ecotrons sent me a replacement for 128g/min, Matt said all the new kits will come with the new injectors. I'm hoping to see a better response at the top end, but I have not yet tested to see if the top speed got higher.
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I'm guessing you got this information directly from Matt. It's a little confusing to me because I'm used to reading injector stats written in either cc/min or pounds/hour.
So to get cc/min I have to go through the following:
The 80g/min injector = 80/453.6*60 = 10.5pounds/hour which converts to 110cc/min
and the 128g/min injector = 128/453.6*60 = 16.9pounds/hour which converts to 177cc/min
(the 453.6 factor is "grams in a pound")
So the Ecotrons kit now uses 177cc/min at 43.5psi injectors. That's definitely an improvement and may actually be the perfect injector size for the EX-250. As a comparison Kawasaki uses 200cc/min injectors in the fuel injected EX-250.
The reason I say that the 177cc/min injectors might be exactly perfect for the EX-250 is this:
In my EX-250 project I used the Kawasaki OEM throttlebody and its 200cc/min OEM injectors. When I finally had my bike all up and running and properly tuned my idle-speed injector pulse-length (at fully warmed up engine temperature) is a 0.7 millisecond shot of fuel at 42psi. All of my do-it-yourself fuel injection expert sources say that you don't want to go any shorter than this at idle because below that pulse-length the math becomes problematic for the ECU and the injector itself can't react precisely enough to provide tuneability.
(As a side note: I'm pretty sure that for the fuel injected EX-250 Kawasaki just used an injector that was already in their parts-bin. They figured out that the 200cc/min injectors were just barely small enough to work, so they went with them. It's very possible that these same injectors are in the Ninja 650R.)
So with slightly smaller injectors, 177cc/min in the Ecotrons kit, you should find that they're easily tuneable for idle (it'll probably around a .9 to 1.0 millisecond shot) and they'll also have plenty of fuel flow-rate capacity to feed the bike's 125cc cylinders at 13,000 RPM.
It's in the high-RPMs that the original Ecotrons 110cc/min injectors ran into problems: At 13,000 RPM the 4-stroke engine cycle (720 degrees of rotation, which is two full engine rotations) takes .00923 of a second (60/13000=0.00461*2=0.00923). Or you can phrase it as 9.23 milliseconds. That's all the time you have to get the needed fuel through the injector and on its way down the intake tract. And you have to include "injector opening time" of about 1 millisecond for the electrical signal from the ECU to cause the injector to open. So now you're down to working with 9.23 - 1.0 = 8.23 milliseconds and the 110cc/min injectors just didn't flow fuel fast enough. Maybe it was just barely too little, but aparently it was pretty noticable in some of the early installations.
So it sounds like the Ecotrons kit is improving.
The "take-away" message for people building a do-it-yourself fuel injection project is that with injectors there is a relatively small flow-rate size range that will work for any particular engine size and configuration. If you're not careful you can end up in an un-tuneable situation with injectors that are too small or too big.
(Unlike everything else in America "bigger isn't necessarily better")