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Torque Curve

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So I think I've got my YZX pretty well tuned what with now having the head mod done and the STIC metering block but one thing that's still bugging me is that it feels like the power curve drops off too soon in 3rd gear. Maybe this is normal for the bike and just in it's nature but I just feel like it ought to pull a little harder and longer but it goes flat pretty fast. What would that indicate, lean/fat jetting or just nature of the beast?

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Hmmm.  My YZX always blows me away with how long it pulls on top--even with the FMF Gnarly I have on it now.  Fat main jet could cause this, although with the STIC I would think you would have to be VERY fat up top to cause this, if I understand correctly.  I thought that's where the STIC was the best, was way up in the revs.

Where is your timing set?  Advanced ignition timing could also have this effect.

My bike is bone stock except for Twin Air filter, jetting for my conditions, PV shim removed and FMF Gnarly.  The thing pulls good down low, and revs out and actually pulls farther than any "standard" YZ250 I've ridden.

FWIW (and this won't apply to you with your STIC) I'm usually around 3500-5000 ft.  Jetting is:

45 PJ

N3EJ #2

172 MJ

It runs a bit fat at low throttle, but I tend to ride where there are long downhills so I feel safer like that.  It doesn't load up though, ever.

Edited by Doc_speeder

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No it feels pretty good in the other gears but if there is an issue with the main that's affecting 3rd gear pull (RPM range) then I'm sure it's affecting everything. I'm riding at 4500 and about 60* right now but I've noticed this issue at 3000 with different jetting as well.

I was recently running a 180 main but with the STIC meter you're supposed to run 5 steps higher than you would with OE meter. For my last ride I dropped it to a 175 and that seemed to improve things but it's hard to tell, for sure still falls flat pretty quick IMO... Of course I've been riding a 450 XCF for the last 4 yrs and trade back and forth between the 2 bikes often. The 450 pulls and pulls and pulls so that could be tainting my perception as the 2 bikes are not much alike. I have had many 2ts in the past though and don't recall them feeling this way, guess it's time to try a different main, and and I'm running the Zuk CJ needle.

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