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How the hell does this FCR 39 ap timing screw time anything??

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Ok. I'm trying to tune an FCR 39 to work on my drz... I couldn't afford the $800.00 kit so I'm rolling with a 2002 wr fcr model. Anyways I was trying to time it to not hit the slide but in or out all the way its the same. The more i turn the timing screw in the longer my squirt duration. (Up to 3 seconds) the farther i back it out i get less squirt duration. I don't understand why everyone says to adjust this to time when squirt starts. The only thing i see that could affect squirt timing on  ap circuit is the cam on the throttle shaft. Or by screwing the timing screw so far in the spring binds up and it pulls the rod away from contacting the ap diaphragm, but i don't think that's how it's accomplished. As far as i can tell right now, if i lightly get on throttle, fuel slightly contacts slide. If i open her up quick it misses it.. but it's the same 3 turns in or backed all the way out..

 

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Where is the gap supposed to be? Do i screw the timing screw in until it pulls the rod off the diaphragm? The spring holds the black piece against the timing screw unless i back it all the way out than the diaphragm is fully compressed so there is no room for fuel....

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Where is the gap supposed to be? Do i screw the timing screw in until it pulls the rod off the diaphragm? The spring holds the black piece against the timing screw unless i back it all the way out than the diaphragm is fully compressed so there is no room for fuel....

Screenshot_20170425-172551.png
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Thanks! Where did the 2.75mm come from? I still don't see how turning that screw in delays squirt. It seems to just allow the diaphragm to open more and let more fuel in. As soon as throttle is applied and the silver lever moves the black one moves simultaneously.. there is no slack to be taken up that would cause a delay... Maybe I'm missing something

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I don't remember exactly how I set mine, but taking the rod off the diaphragm seems familiar. Try extremes and see what gives you the slight pause when the slide opens.

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Thanks! Where did the 2.75mm come from? I still don't see how turning that screw in delays squirt. It seems to just allow the diaphragm to open more and let more fuel in. As soon as throttle is applied and the silver lever moves the black one moves simultaneously.. there is no slack to be taken up that would cause a delay... Maybe I'm missing something

The screw controls the preload on the diaphragm, which then changes when it shoots. I assure you it definitely changes the timing. If you're not seeing an obvious change then I suggest you further investigation the condition of all the parts.

 

The picture is from JD Jetting's website. I'm not sure if the value was lifted from a OEM manual or what, but it will get you close.

 

 

 

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