Pinging after PowerNow and PowerNow Plus

So I have a '08 KTM 250 XCF-W. When 100% stock, I had a little bit of pinging at low rpm, high load (lugging) conditions. I got the JD Kit, ran the recommended settings (180 Main, Red needle 4th clip) for it and it got rid of the decel pop and the pinging. It ran great. Then I decided to install the PowerNow and PowerNow Plus. I left the jetting as it was, but got a little ping while lugging, similar to it was when completely stock. Then, I dropped the clip to Red #5, and it seemed to help a little, but not enough. I then double checked the fuel screw to Eddie's recommendations, and it came out to be about 2 3/4 turns out from fully seated. Then, I decided to go all out and go the the Blue needle, clip #5. Here, I have even more ping under lug than before, which doesn't make a whole lot of sense since the blue needle is supposed to be richer. Now I'm out of ideas.


Get rid of the Power Now stuff. All that will do is mess up your jetting and slow your bike down. Reset the jetting as it was before you installed the gimmicks.

Your results are a perfect example why these devices should not be sold.

Ok, I went back to Red #5, but swapped out the #42 pilot for a #45. Seems to have helped. We'll see when I hit the dirt a little more. I did have to turn the fuel screw in about 1 full turn from where it was with the #42.

As a side note, turns out that the pilot jet for the 39mm FCR is the same pilot from a 2 stroke PWK carb. I couldn't find anyone in town with a #45 pilot, so I looked at my old JD kit for my 03 RM250 and just by chance, they use the same pilots.

Your fuel screw 'change' sounds about right. Did you leave the PN stuff in?

Yeah, both PN and PNP are still in. I do like the bit of low end that they added. Before I did any of the jetting/PN changes, I'd gone with +1 tooth on the countershaft sprocket to make 1st gear more usable. It seems like the little bit of grunt I lost to gearing was made up with the PN/PNP.

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