Big Bike Advice!

Hey, my brother just got a 1999 YZ-400f and it needs to be jetted. And we are looking for some advice of what size jets we should start with. We live in Albuquerque, NM and that is at about 6000 ft. And during th summer it is like in the 90's to ride. The bike also has a FMF PowerCore IV exhaust on it. What size jets do you guys run? Thanks a ton for the help.

go through the jetting specs sticky!

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