Jetting question

Just got an 03 WR450 and it has the quick throttle bog. I have a JD jetting kit and am curious the settings. I am at sea level, 95+ degrees and high humidity. All the free mods have been done, the rest is stock.


Elevation 0 to 4,000. feet

30 to 45 degrees: 172 main, JD Blue #5, 48 Pilot, 2.0 turns, 75 starter jet, #0 leak jet

45 to 60 degrees: 170 main, JD Blue #4, 48 Pilot, 1.75 turns, 72 starter jet, #0 leak jet

60 to 75 degrees: 168 main, JD Blue #3 or JD Red #5, 48 Pilot, 1.5 turns, 70 starter jet, #40 leak jet

75 to 90 degrees: 165 main, JD Red #5, 48 Pilot, 1.25 turns, 68 starter jet, #50 leak jet

90 degrees plus: 160 main, JD Red #4, 45 Pilot, 2.0 turns, 65 starter jet, #60 leak jet

There you have it...SC

Those settings quoted above include high humidity regions of the midwest and south that require leaner jetting then dry hot California and Arizona type weather at the same temperatures. :)

Thanks everyone for your help. I will give a try this weekend.

Well guys, I still have not found time to look into my jetting issue, will be doing it tomorrow. I more question, where is the main jet located and how do you know what size it is. It is probably stamped on them, I just have not got out to look at it, wanted to find out beforehand.

Thanks again.

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