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Jetting was never my fortè


Rage_kage

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I just finished building my bike and I'm having issues with 0-1/2 throttle on take off. Its basically falling flat on its face and bogging till it shuts off. It idles fine I can stab the throttle and it responds fine. But I just can't get it moving unless I feather the clutch and get it in the higher rpm range. I tried the excel worksheet and its giving me really high numbers. So if you got any input that would be great.

 

>Heads cut .15

>Stock cylinders 64.50 with a fresh top end

>Stock bottom end

>Stock carbs currently running 300 main, 30 pilot and the air screw in the stock pos.

>Cfm airbox with uni pods, its not on the quad yet, I left it off to sync the carbs

>FMF fatty's

>I'm at roughly 1200ft above sea level

>Its been in the 40's lately.

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Sure you have the slides in right?

 

Your jetting is pretty damn close for what your setup is. Have you tried dropping the pilot to a 27.5? My experience with FMF pipes is they like a little larger pilot than other pipes. You kind of need to figure out if you are dealing with a rich or lean issue. You you tried playing with needle position at all?

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Sure you have the slides in right?

 

Your jetting is pretty damn close for what your setup is. Have you tried dropping the pilot to a 27.5? My experience with FMF pipes is they like a little larger pilot than other pipes. You kind of need to figure out if you are dealing with a rich or lean issue. You you tried playing with needle position at all?

I have not its in the 3rd clip, I bought a Vito's jet kit as well that has the larger size jets and it included needles so it has Vito needles...
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What kind of needles do u have? What clip are they in? What kind of reeds? Does it pull clean up top? Have you done a leakdown test? 30 pilots are good enouph to get u going with your set up and mains are damn close to my guess is there's something else wrong if it's shutting off with those jets, . My first step would be leakdown test , compression test, adjust cable play, ohm plug caps, gap spark plugs, start bike sync carbs, . If all other areas checked out ride bike if problems continues move needle all the way rich to start if prob gets worse move needle all the way lean. Fine tune needle from whichever point helps . Or ignore everything I said to check and ride it till it blows and then say I don't understand why it blew lol !!! Sorry for the rant , don't be a statistic make sure it's mechanically sound

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What kind of needles do u have? What clip are they in? What kind of reeds? Does it pull clean up top? Have you done a leakdown test? 30 pilots are good enouph to get u going with your set up and mains are damn close to my guess is there's something else wrong if it's shutting off with those jets, . My first step would be leakdown test , compression test, adjust cable play, ohm plug caps, gap spark plugs, start bike sync carbs, . If all other areas checked out ride bike if problems continues move needle all the way rich to start if prob gets worse move needle all the way lean. Fine tune needle from whichever point helps . Or ignore everything I said to check and ride it till it blows and then say I don't understand why it blew lol !!! Sorry for the rant , don't be a statistic make sure it's mechanically sound

Vito's needles

Middle clip

Carbon tech reeds

No leakdown yet

Haven't done a compression test but I know its putting out.

And its a ignorant bastard on mid to top end.

 

I understand the importance of jetting, I get where your coming from I've seen the after effects of lean jetting and I don't want to be one of those guys

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