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stock 42 pilot jet oddity

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I have a 2015 X with like 300 miles on it. Motor is stock except PAIR valve removed and added fuel screw. Bike runs great, but my fuel screw is set at 3/4 out, which is well in from the recommended 1 3/4 out. Not complaining as it runs good ,but it seems like all I have heard about the bike's being lean from the factory I would have thought I would be like 2 turns out. But based on adjusting the idle with the fuel screw, 3/4 is good in warm weather, and 1 turn out in cool weather.

If I set the fuel screw at 1 3/4 it seems I get a slower return of the bike to a good idle after throttle use. Wouldn't that indicate a rich condition with too much fuel? It improves as I turn in the fuel screw. (leaner) Thoughts?

Edited by dogeddie

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When you removed the original fuel screw, maybe some tiny washer or o-ring was forgotten in there ?

If so, I'm thinking any extra thickness would push out on the needle, making the circuit run richer.

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Jim Dettman said in another post:

 

"Let the motor tell you what it needs.  On a warmed up motor:

 

1. Lower the idle speed till just running.

2. Adjust the fuel screw for smoothest idle.

3. Repeat steps 1 and 2 until you can't keep the bike running.

4. Raise the the idle to 1,7000 rpms.

 

If the bike pops on decel (assuming you have the smog pump off) or has a hanging idle, turn the fuel screw out 1/4.

 

You want the fuel screw to end up between 1 and 2 1/4 turns out.   If <1, then the current slow jet is too big.   If > 2 1/4 turns out, then the current jet is to small.

 

Once you have this dialed in, a quick check can be performed (again on a warmed up motor and at idle).

 

1. Pulling the hot start *slightly* will cause the RPMs to rise.

2. Pulling it all the way will cause the motor to die.

3. Pulling the choke out will cause the motor to die.

 

 The above means your slightly rich on the slow (idle) circuit, which is where you want to be."

 

 

So I did that tonight and 1 turn out is good. It's after a heavy rain and a humid 67 degrees. Pulling the hot start caused the RPMs to rise slightly, pulling it all the way in killed it, and pulling the choke killed it. For reference though:

1) If the hot start pulled in slightly did not increase RPM, what would that indicate?

2) If pulling the hot stert all the way in did not kill it, what would that indicate?

3) If pulling the choke out did not kill it, what would that indicate?

Thanks!

Edited by dogeddie
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