i'm about 800-1000 ft above sea level
motor is .030 over
fmf fatty gold series pipe
fmf power core 2 silencer
uni filter w/ air box lid on
boyesen carbon fiber reeds
intake and exhuast porting
Klotz supertechniplate @ 32:1 with 93 octane
NGK BR8es BPR8es

motor is brand new..all new crank selas and bearings, piston, rod, the whole works!!!

stock carb...keihin 34mm. air screw is 1 3/4 turns out. only thing i messed with was moved the needle from the 3rd clip to the 4th clip, and put a 165 main in for break in.

i tried a 160 main, but seemed a bit too lean.

here's the condition:
-sputters really bad from 1/8 to 1/2
-wide open seems ok, but i didn't want to push it too hard yet becaus the motor has only had 2 tanks of gas through it.

plug looks a bit lean when i check it.

would this be the pilot? or would the needle?

yes the filter is cleaned and oiled
yes the pre-mix is new

 

If it sputters on the bottom-end, most likely a too large pilot jet.
The only way to get it close, short of running an exhust temp gauge, is to do plug chops. Yes, you can do bottom-end chops as well as top-end. You're not going to hurt your new motor doing them if you do them properly.
Go back to the .165 main jet and put the clip back in the middle. If you can do without it, toss the air box lid. You don't need it unless you're riding in extreme mud/water. That will let it breathe better.

 

If you have the money just ditch the old carb and get a new pwk or whatever you prefer. The brass seat that the needle moves in and out of gets worn over the years.
I hard time with jetting until i bought a new carb. The PWK's are a tight fit in the air boot though.

 

Darrin is right, if you can shell out the $170, get a new AirStryker 38MM. No more headaches and far better performance than a stock carb.
You're main sounds fine, when it's sputtering where you say it's sputtering is not a main jet problem, check pilot and toss that lid, you don't need it. I can't remember but one of the past few months DW's had a good article on jetting, I think it was DW's anyway.