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Jetting issues yfz, tried everything

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Okay I will start with the current settings


3000 ft

GYTR slip on

Box lid removed

Stock filter

Cam mod

Dyno jet kit (all jets listed are DJ)

DJ 144 main

DJ pilot 48

DJ needle 5th clip

AP timing and duration set to factory specs

2 turns pilot screw

Heres the problem, after a few long hard full throttle pulls the bike falls flat on its face as if it were out of gas, dies, the only thing that keeps it running is the forward motion with the clutch out. theres also a popping on deceleration problem, but I assume that a lean main (correct ?)

Is there a temp switch that shuts down or retards the timing when a lean condition causes the motor to over heat ? a fuel cap not venting, or a carb float thats not filling the float bowl ?

It didnt do this before I started messing with the carb, so i'm pretty sure its carb related.

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Nope, I already checked that. the fuel flows well without the carb attached (petcock open) and just as well with the float bowl off.

I keep coming back to the bowl though, is there a possibility a float could cause this by not allowing enough fuel to return to the bowl when it should be wide open ?

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Okay problem solved, I checked the float height, but it was already at factory height...or so I thought.

The recommended height is 8mm, but the manual states that it should be measured without the valve compressed. Once I checked it without the valve compressed it was WAY off. I re-set the height and with a main and ppilot change everything is now running smooth.

Thanks for the help

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