Jetting Husaberg 650 Akrapovic Titanium HELP

This graph is 100% a figment of my fevered imagination, and is only to be used as a general guide, not an absolute definitive end all be all word of truth. That said..

1. air jet way too small
2. air jet a little bit too small
3. air jet just right
4. air jet a little bit too big
5. air jet way too big

So basically what happens is if you have the mixture right at low rpm, and it's too rich at high rpm, the air jet is too small and you need a bigger one. Or if you have it just right at high rpm and it's too lean at low rpm, you have an air jet that's too small and you need a bigger one. Or if you have the mixture just right at low rpm and it's too lean at high rpm, the air jet is too big and you need a smaller one. Do I really need to type the fourth combination? When you put in a bigger air jet, it leans things out everywhere, but more at higher engine speeds. And when you put in a smaller air jet, it richens things up everywhere, but more at higher engine speeds. Then when you get the right air jet, it might be too rich or too lean everywhere, so now you have to go and put in a smaller or bigger fuel jet to fix things up again. So you control the shape of the graph with the air jet, and move it up and down with the fuel jet. The same thing is supposed to apply when working with the main air jet and main fuel jet, but it doesn't on FCRs, for reasons which I'll get into further down. But it's supposed to, damn it.

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If you find that the engine runs perfectly at WOT near the torque peak, but becomes lean toward redline, select smaller main air jets. Conversely, if the engine runs perfectly near the torque peak but richens toward redline, select larger main air jets. Changes in air jets may require changing the main fuel jet. Say you have good performance at engine speeds leading to the torque peak under wide open throttle with a 150 main fuel jet and 200 main air jet. Should you need to richen the mixture at full revs and full throttle and select a 180 main air jet, you may need to go down to a 145 or 140 main fuel jet to keep the lower rpm mixture the same as with the 150/200 combination. Generally (there are always exceptions), once the main air jets are properly selected for the intended application, they need not be changed again unless you change the intake restriction (modify the airbox or use different filter) or change engine or exhaust specification. Varying atmospheric conditions can usually be dealt with by fuel jet, fuel screw, and needle changes.

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