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'05 KTM 400 EXC Elevation Jetting Sanity Check

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Heading to Colorado soon, will be riding 7,000-13,000ft.
Normally ride 700 to 3,500ft in GA.

Current setup which seems to work well is 178 & 45, OBDVR needle using 5th slot down from top.

Following this jetting chart http://www.ktmamerica.com/ktm_jet_chart.php
I should be using a factor of 0.88-0.94 for my CO trip (7-13,000'). I settled on 0.9 which leads to a 160 & 40 and moving the needle down 2 positions.
However, I emailed the previous owner who took the bike to elevation in Colorado several times, he said the best all around performance he experienced was with the bike set up exactly the same as it is now. Doesn't seem to make sense?

When I took my XR400 to Colorado a few years ago I just followed the Honda chart to jet down and it worked well, so I'm inclined to do the same thing here. 

So, should I follow the chart or leave it as is and assume the color orange bends the laws of physics?

Edited by CruisinGA

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That jetting is 0-6000 for sure

I would at least bring a pilot and a main, as you can change them without removing the carb, if you have a jet port on your floatbowl cover.

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If it were me, I would do what you suggest...lean out each carb circuit before you leave...
I am getting happy with a jetting set up on a couple of 2 strokes that operate from about a 1,000 ft to 4,000 ft range in riding altitude, here in So AZ. If I were planning a trip to ride 7,000-13,000 ft of altitude I would expect to install a smaller pilot, drop the needle (raise the clip), and go down a size on the main...but I have never done it...maybe, someone has...
Once I got there, I would then expect to tweak the airscrew for best idle, once the bike had been ridden a couple of minutes. Then, I would start judging whether the mid-throttle needle position is correct...
Then, I would buy a Lectron...

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