I have a 400ex 03 curtis sparks air filter with lid on box, and i am gettin a dg hp2 exhuast system, i live in nj and its 60 to 65 degrees all year.


What size jets sould put in..?
( very new to jets i had a cannondale before jus got 400ex)

 

I would try a 152 or a 155 Kehlein main jet.