[JerryHawk250]

Originally Posted by Ratbagger

Interesting stuff to hear about the ECM guys, thanks.


I got a KPX 250 in August and from day one it had idle issues. It has improved over time a bit but the problem has been that when left idling or if I rev high while riding and suddenly pull the clutch and hold it, when it drops to idle, it may stall. It's improved enough over time that it rarely happens now at ~700 miles but I'd like to fix it.



I previously attempted adjusting the TPS as shown in some videos you can find online but that didn't help at all. Actually it made it worse, so I put it back where it was. I've been thinking that I need to adjust the idle set screw and bump the idle RPMs up by a couple hundred, and I've already attempted to do that, but ran into a problem. After taking off the plastics and getting access to the idle screw I found I couldn't separate the grub screw from the nut. The grub screw calls for something like a 2 or 4mm hex wrench, very small, and it stripped/rounded off when I tried to twist it out of the nut. Since then I've been planning on getting a new idler screw and nut. If anyone has any info on a nice replacement, something like a knurled thumb screw would be really nice.


After seeing this thread though I have to wonder if maybe I can send in the ECU and get it fixed that way. I also notice some popping sounds occasionally that seems to happen most often during engine braking. I've heard this is typically overly lean fuel mixture. Maybe connected to the idle issue and the ECU reprogramming would fix it.

You can send the ECU back to American Lifan and they will reflash it.