I'm sure you right about the API Tech ECU..

But it is safe to assume that this detune is "here to stay" on all the new (and old) EFI KLX's - point being, if you have found, or know of, other options that might work, we all can learn very quickly how to work the software/interfaces..

Your bike is at the forefront on this, and it also has the most to gain - right now - from any "fix" that can be found.. I am still convinced, from similar 351 carb'd mod combos' power levels, that you are not seeing about 5hp due to this detune.

 

Those are my ideas on the detune and the way to fix them. I am pretty confident, as well, that about 5 or so horsepower is being left on the table. New parts should be coming for the KLX after the first of the year. So, we'll see how it goes then.

 

Ok @J Higgens , I did a little research in here regarding the API ECU..

Seems this is "ancient history" for us - the detune process used by the ECU, etc etc...
It is easy to understand why we don't know this info (that we have in here) - the EFI guys in here have always been a very small subset of the membership and us "Carb" guys generally don't read the little bit of technical EFI stuff they've posted in our past..

So, here is the thread with all the info. It is a long and difficult read but a MANDATORY read for those interested in unleashing their EFI's..
https://www.kawasakiforums.com/forum...-klx250-36083/