450r carb on 400ex

[atvjunky57]

i just rebuilded my 400ex put a 416 piston n rings 11-1 comp, hot cams stage 1 n i got a 450r carb n was wondering if i was going 2 have 2 jet it n im at sea level. or am i just going to beablr to bolt n go? need some input

[tri5ron]

You will need to rejet.
All bikes run differently, even with the same mods.
No 2 bikes, even with the same mods, will jet exactally the same.

You can ask "what is the jetting I should have",...

But in reality,
if you want it to be spot on,
you will need to jet it yourself, or have a competent dyno shop do it for you.

there are MANY threads in the "how to's" section of the forum, and "most popular"section at the top of the 400ex forum, that discuss proper jetting.

It is one of the most commonly asked questions here, ESPECIALLY reguarding the application of the 450R carb on the 400EX.
You should easily be able to find any and all the necessary info in those threads.