Carburetor expert needed 07 YZ450f @ 5000ft altitude

I have a 2007 Yamaha yz450f. I live at 5000 ft above sea level and need advise. I have read some members say the stock jetting setting are a lean setup at sea level. I have used an excel spread sheet that says at 5000 ft and 70 degrees I should be running a 152 main jet, a 42 pilot jet, and the needle setting at 3rd position. I have not tested this new setting but when I had it set to a 152 main, a 42 pilot, and needle at 4th groove I would run lean and have a great amount of back fire on deceleration. I don't want to damage the motor by running lean, so I was thinking of going with a 157 main, 45 pilot and clip position 3 on the needle. Anyone have experience at this altitude with an 07 yz450f? HELP? Grayracer513 are you still around?

I've successfully ridden my YZ'D WR 450 at that feet. With normal jetting and it ran fine.

Decel popping is only the pilot jet. You can get less popping with a larger pilot. But it will still pop on decel.

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