Jetting with an HMF

[Green95Hoe]

First off, im gonna apologize up front for what may seem to be yet another posted question without searching. All I found was jetting for the 450. Hopefully I can find someone who has my setup and save myself alot of time.

I bought my 400 used with a stock pipe but I have reason to believe it was jetted before I bought it and the shop put the stock pipe back on. Today, im running an HMF Bill Ballance Slip on, factory headers, K&N and outerwear built into the lid. Im also considering scrapping the choke since Ive never once come close to needing it. Looking to know a comfortable main jet size. Ive been guessing 160 based on what ive heard but I need second opinions. I dont even know whats factory. Thanx in advance fellas

~Brad

[hawaiiansupaman]

im running 160 MJ with the stuff in my sig. also lid off a little rich but it works

[jak1389]

stock main jet is 148. i am running a 160 main 40 pilot needle on the 3rd clip, and no clue about the fuel screw, i just adjusted it until it was perfect. just start off at 155 at if its too rich go down a size too lean go up. just start from somewhere you think is close.

[400exstud]

I am running a 160. May be a bit rich but better safe than sorry. (I don't foul plugs much so......:o )

[Green95Hoe]

Wow, thanks guys. That answers my question.

~Brad

[04'400ex'er]

Originally posted by hawaiiansupaman
im running 160 MJ with the stuff in my sig. also lid off a little rich but it works Dynojet are bigger than stock jets. 160 main should be a close start though. maybe a 42 pilot.