rejetting

[sparta4188]

Do i have to re jet if i get a new exhaust and a 440 kit for my 400ex,

If i just get a 440cc kit do i still need to rejet.

If i get an exhaust do i have to rejet.

i know you need to but my dad doesent really knopw what that is and things, so could you explain it.

[Honda#4]

Anytime you increase flow or air you have to rejet. I think if you add a 440 you still have to rejet.

[hornetgod13]

Yes you would have to rejet. Jumping to a 440 is significant. You'll need more fuel to feed that monster. Consider increasing the air flow in to the carb as well.