Jeff Langston _ Carb Settings

Here are the Carb settings you asked for:

YZ/WR400F 0 to 8000 Feet.

Needle: OBEKN on clip #3 from the top

Pilot: 38

Pilot Air Screw: 65

Alternate Pilot: 40


Main: 155

Main Air Jet: 160

Fuel Screw Initial Setting: 1/4 turn OUT

Additionally You will need to purchase an RC wheel Collar and attach it to the Fuel pump rod from normal rest position UP the width of a dime and tighten the collar. (TAFFY MOD)

Ride with caution because the bike will now rip your arms off.

Good Luck,

Bonzai :cry:

Ride with caution because the bike will now rip your arms off.

Good Luck,

Bonzai :cry:

I can vouch for these settings...I setup my carb this way exactly upon Yamakaze's recommendation and now my YZ400 rips like I can't believe. The bog is totally gone, and my front tire is rarely on the ground!


You still hanging around Jeff ???

Bonzai :cry:

WOW who thought changing the pilot jet could make so much difference and never has it started so easy :cry:

I did things a little different though

165 MJ ( change to 160 or 155 possibly )

stock 200MAJ ( I still need to order a smaller MAJ but I was wondering It rips up top would going down on the MAJ make it so I could run a leaner main without decel popping ?)

JD blue needle 4th clip ( James said it was similar to the OBEKN needle with this clip position)

40 PJ (might try a 38?)

70 PAJ

1 sec on AP with taffy mod

1 1/2 turn on fuel screw

It is a blast to be crusing along with the throttle closed and whick the throttle and loft the fron end with no hesitation :cry:

Thanks for the help with the jetting tips Yamakaze, Pothole and James Dean.

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