klxster, I have a 2019 KLX250 that is 100% stock right now as far as engine performance is concerned. Stock exhaust, stock air box lid, everything. I want to at least go lidless with an FMF PowerCore and I’m at a point where the options for fuel tuning are confusing me. I was just reading threads that talk about the stock ECU’s soft limiter and how it reduces power at high RPM. I got into old discussions here and on other forums about the API standalone ECU that eliminated this problem through custom maps, but since API appears to no longer be in business it would seem that Dynojet would be the next-best option. Originally I was going to go EJK, but my concern is that despite the EJK being the cheapest and seeming like the easiest to use, that it would still not solve the high RPM soft limit which obviously I would like to eliminate.

Now here’s the thing: If I did the clutch jumper mod, is that enough of a fix to then use the EJK and have good fueling across the whole tach? Or would that combo *still* not give me the proper high RPM fueling and ignition timing?

 

At this time, there is no known working "fix" for the soft limiter programming in the stock ECM. We are doomed to see all top end power levels killed by the computer until a flash tuner becomes available OR if testing proves that it is possible to defeat the majority of the programming with a PCV.

Doing the clutch switch mod, adding an EJK, running the lidless EJK settings, is the best we can do at this point in time.

 

Thank you for the insight. Does this mean that spending the extra money for a PCV over an EJK or PCFC is basically pointless at this time?

In terms of the clutch mod, I'm not sure I understand what the point is. J Higgins says there was no difference on the dyno when he did it. Does it actually affect US bikes?