jetting for a '00 YZ426F w/ Power Core 4

I just put an FMF Power Core 4 with Power Bomb header on my other wise stock '00 YZ426f and was hoping someone with the same set up could point me in the right direction on jetting. The bike runs good, loud but good, but I'm sure I'll need to rejet. Normal temp for a ride( dualsport street riding ) is about 116 degrees. A ride this afternoon and the bike ran 135-140. Hotter temp to me would mean lean condition but do I jet pilot or main? Slight surging at steady 45 mph( 14/49 gears ). Any help would be appreciated.

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