stock jet size (400ex)

[4oorider]

does anyone know the stock yet size. the one i took out had the keihn logo and a 148. my brother who is a genious with engines and stuff wont believe me cuz hes putting in the new jets.

[walker054]

stock main jet = 148
slow jet =#38

[NCexRider]

Stock main jet is 148, stock pilot jet is 38.

[4oorider]

any one know what a good jet size would be for a K&N and a slip-on, we cant seem to keep the engine running

[NCexRider]

155

[4oorider]

thanks very much, its running now, now its time to ride:devil:

[quadman 05400ex]

when i got the 05 i got a quad works atv power up kit it comes with high flow air filter and a jet kit and prefilter BUT its for 99 to 03 and i had a dg oval but i got a yosh and my step dad says the jetting is way to big im wondering if that true:confused: