440 jetting.

[2003TrX400eX]

Just built to a 440.

White bros e series, k&n, no lid.

Getting black smoke when I hit it hard, but there's a hiccup through the air filter when I'm riding at a steady throttle. Gonna be jetting this weekend, just need some starting point. Around a 170? now, and a 42 pilot. Screw 2.5 turns out.

Also, I'm on the Michigan/Ohio border.

Thanks.

[Ryan02400ex]

I'm running a 426 11:1 with a slip on and k&n filter and I'm far to lean at 165. I'm getting different jets soon. I would probably go higher

[2003TrX400eX]

I'm gonna use johns method and start with the biggest jet I got.

[Ryan02400ex]

What size is it?

[2003TrX400eX]

I think the biggest one i have is around 180.

[cheater13]

Originally posted by 2003TrX400eX
I'm gonna use johns method and start with the biggest jet I got.
Good plan. That's who helped me do my jetting on here. If your 180 is still too low, buy them in increments of 5 from 185-200. Their only 2.99 apiece on jetsrus's website so it won't hurt to have a few extra jets.

[DragonGunner]

I run 180 with the needle raised one notch. Good for 50 degrees on up....for colder I throw the lid with some 1" holes on to richin it up.

[JOHNDOE83]

I would think just by guessing you would be tween 190 and 215.

My modded 440 motor uses a 220 main jet but a milder built 440 thats at a higher elevation then me uses a 190.

I figure yours is mild enough but also big enough to be 190 or more possibly.

I would get between 190 and 215.

The hiccup is deffinetly lean, more then likely at the needle but might go away if you turn your af screw out to 3 or 3.5 turns.

If not raise the needle by moving the clip to a lower notch.

42 should be fine if the needle raise stops the hiccup.

I still reccomend atleast 3 turns on the af screw.

[2003TrX400eX]

Ok thanks a lot guys.

Gonna try to mess around with her this weekend.