2010 YZ450F Acceleration Bog

I have a 2010 YZ450 that has a nasty bog when getting on the throttle hard.  The bike has 85 hours on it and the bog didnt start happening until about two weeks ago.  I ride mostly on a motocross track.  The bog happens right when I need the power the most, on the face of a jump.  It feels like I am pressing the kill button.  The bike has never died, just loses all rpms.  The bike had 4 historic codes on it; atmospheric pressure sensor, throttle posistion sensor, intake air pressure sensor, and coolant temp sensor. I have replaced the stator/pick up coil and the kill button, neither of which have helped my issue. I have checked valves, all sensors, and wiring per the service manual and have not found any problem. Does anyone have any idea whats wrong with my bike? I feel like it is an electrical issue and not mechanical, as the bike always starts right up and runs great until the bike is hot. I am yet to determine if I am losing spark or fuel when the bog happens. 

Its most likely the fuel pump, mine did the same on a jump face or when I lifted the front to get over a whoop etc

I have had a fuel pressure guage on the bike and it has never lost pressure, it holds steady at 48 psi.  I double checked all the wiring again and found a connector that is not listed in the service manual anywhere.  It is on the right hand side rame rail on a bracket that holds the atmospheric pressure sensor.  You can access it by taking out the airbox.  The connector is a hub for all like color wires to come together.  I took the connector apart and found that I had corrosion on one of the ground wires.  I cleaned it all up, put it back together, and took it out riding.  So far I have not gotten the bog to come back.  Im hoping that fixed my issue.

I have had a fuel pressure guage on the bike and it has never lost pressure, it holds steady at 48 psi.  I double checked all the wiring again and found a connector that is not listed in the service manual anywhere.  It is on the right hand side rame rail on a bracket that holds the atmospheric pressure sensor.  You can access it by taking out the airbox.  The connector is a hub for all like color wires to come together.  I took the connector apart and found that I had corrosion on one of the ground wires.  I cleaned it all up, put it back together, and took it out riding.  So far I have not gotten the bog to come back.  Im hoping that fixed my issue.

keep us posted. That's good info to k

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