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Old 01-08-2020, 03:35 PM
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Default 2002 YZ426 fuel screw adjustment

I have a question about fuel screw adjustment on my 2002 YZ426, book says 1 3/8 turned out from all the way in? My bike runs good at 2 1/2 out just like basanch 73 said. I go by the book when I work on anything why would we be at a full turn + to run good?. Thank you
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Old 01-18-2020, 01:14 PM
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Elevation, temperature, and humidity all pay a role in jetting. If you consistently need to run it 2.5 turns out, I would probably suggest going one size larger on the Pilot, but since it's cooler now, that seems to make sense.

If I'm thinking about that correctly.

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Old 01-19-2020, 12:38 AM
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The fuel screw is an every day and ride adjustment and is not a fixed setting. The manual gives you a place to start at sea level. Most bikes with that carb call for about 2 turns out as a starting point, so you are not that far off.

Paw Paw
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Old 01-21-2020, 10:08 AM
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If I recall between 1-1/2 turns and 2-1/2 turns is considered normal range. If you run the fuel screw out much farther than that you risk it vibrating loose and falling out of the carb.
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