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04 KTM 450EXC jetting

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I have an 04 KTM 450EXC and I'm currently running a OCEMN needle in the 3rd clip pos. down from top, 162 main, stock pilot, fuel screw at 1 5/8 turns out. I'm also running a FMF factory 4 pipe and was wondering what are some other if not better jetting combo's and mods? My ALT is about 1000ft:ride:

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flat spot when rolling off idle (could this be something to do with the AC pump squirt starting too late) and flat top end. I used to be able to wind it out to about 172km/h but now it holds around 155km/h.

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any theories????

The OCEMP is a good needle, your entire combo is what I would call "safe rich" or a good starting point to work from. Your off idle will improve if you go a bit leaner on the first stage of the needle (called "L1"), next step (but a micro step that you may not notice would be a OCEMP. I would opt for 2 steps, an OCEMQ. This will give you more of a "lean to rich" transition when you twist, starting from a lean off idle will raise the combution chamber temp and help it burn the fuel of the AC pumps squirt!

As for loosing top speed, with that "E" series needle main jet sizes are very different then the "D" series. 162 is again a "safe rich" starting point. Move down a couple of sizes, I can confirm that 155 is a good number with that needle.

Please please anyone with a "D" series (third from last letter) needle ignore those numbers as a 155 and a "D" needle is instant death to your engine, the "E" needle is a totally different ball game

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Thanks heaps for that info. I will try changing my setting to your suggestions and see how I go. With the OCEMQ needle, do I have to change my main jet size to something other than wat i've got for my OCEMN?

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Thanks heaps for that info. I will try changing my setting to your suggestions and see how I go. With the OCEMQ needle, do I have to change my main jet size to something other than wat i've got for my OCEMN?

As long as you have "E" taper you should be fine in the 155 to 162 area. Its going to take seat of the pants tests to see which (differnce will be very minor)

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