400ex

[new guy]

i have a 2001 400ex it has a white brothers pipe on it how big shopuld i go with the jettin?:confused:

[JOEX]

Originally posted by new guy
i have a 2001 400ex it has a white brothers pipe on it how big shopuld i go with the jettin?:confused:
I had an E-Series with a K&N, airbox lid on with a 150 main jet and it ran great with no problems from sea level to over 3000', ran the same sparkplug for two years too...

[<DRS>GPF]

i ran a 42 pilot and a 165 main.

[JW450R1]

i ran a 42 pilot and a 165 main jet with the air box lid off.no problems

[jsmith2232]

I ran a 146dynojet that is equivelant to a kehein 160 in mine and it ran great, had the same plug in for a year and a half no problems.

[DaleJrFan]

Alot of stuff goes into jetting such as your pipe(full system or slip-on), filter, lid, altitude, what motor mods you have, etc... So give us some more details or do a search on here.