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Hey Man. Its super frustrating. I have had projects I have gotten so burned out on I have pushed them into a corner and left them for a bit and done other things.. it happens.. sometimes you just get stuck.

Set your iggy to 0.. Even though everyone else says .1 MVT in the DD instructions says 0.

Do it exactly like they say, then I would do a leak down test.

I cannot recall if you did one before so do one again, make sure you don't have an air leak. It can make it almost impossible to tune..

Then I would put a fresh plug in, pull the main jet OUT of the carb entirely, and tune both the pilot jet and the needle.

Mark your throttle in 1/4 increments so you know where you are in the range.

Start with the needle you should get ok revs to about 3/4 throttle.. try dropping and raising the needle till you achieve something close to that. It wont be perfect but just close to 3/4 running clean with NO MAIN JET INSTALLED. You may need a fatter or skinnier needle and ideally you want to end up in the middle position + or - 1 position on any needle you install. If you are at the extremes you should resize your needle.


Then with the main still OUT set the pilot jet

as per here

www.shiny-red.net/guides/keihin-carburetor-jetting/

"PILOT JET CORRECT: With one hand on the throttle maintaining RPM at approximately ⅛ throttle,(note: set the air screw in to about 2500 rpm, make sure the rear wheel is off the ground as while you are turning the screw the revs will increase and your scoot can take off!!) turn air screw ¼ turn at a time clock wise until you bottom it out. engine should become slightly erratic and you should have to play with throttle to maintain RPM. Start turning air screw counter clock wise, ¼ turn at a time until you have reached 2 ¾ turns out. Between 1 ¼ and 2 ¼ turns, your engine should have reached its highest RPM maintaining a steady throttle. Adjust air screw again between 1 ¼ and 2 ¼ until you have determined highest RPM. Quick throttle response should be clean without bog.

PILOT JET TOO RICH:

RPM does not reach a peak between 1 ¼ and 2 ¼ turns, stays the same or keeps rising out to 2 ¾ turns.

Correction: replace pilot jet with next leaner and test again.

PILOT JET TOO LEAN:

RPM does not become erratic and engine maintains throttle when air screw is turned all the way clockwise.

Correction: Keihin replace pilot jet with next richer and test again. Remember, with a steady throttle approximately ⅛, there should be a distinct difference in RPM from 1 ¼ turns to 2 ¼ turns if the pilot jet is correct. The emphasis here is to find a pilot jet that will run crisp without bog and without the main jet"

And also

"Jetting Tip: pilot jet and air screw

To check to see if your pilot jet and air screw are adjusted right, warm up the scooter and let it idle as low as possible while still running smooth. From idle, whack the throttle wide open then let it close completely. Listen to the engine. If it bogs right when you whack the throttle open, then revs up, turn the air screw in ½ turn then try again. Do this until it revs up crisply. After the engine revs up, listen to it revving back down. If the revs drop quickly, and the engine starts to bog, and/or die, then you’re too rich on the air screw, back it out ¼ turn at a time. If after you let the throttle off the engine tends to run on and on while revving down very slowly, you’re too lean and need to turn the air screw in ¼ turn at a time. You want the revs to come up from idle quickly and smoothly, then drop back down to idle the same way. If you turn the air screw all the way in and it still needs to go further, then you will need a larger pilot jet. The opposite is also true: if you are backing the screw out so far that it falls out, you will need a smaller pilot jet."


Then put the biggest main you have in it and work backwards. hell even try it with the main out, that will give you a true indication of a too rich condition, pay attention to how it feels and responds, then work you way down your jets from your biggest one till it starts getting snappy.

It takes time, it sucks, and yeah with hyper race it is loud as heck.. The hyper race stuff is also a bit less forgiving in the jet department. In my experience its a bit of a fine line you have to find, not impossible but tricky and because of the peaky power it is a bit more fussy to tune. But learning to be methodical is #1. that shiny red website is probably one of the best step by step tuning guides I have found. (other than they don't tell you to leak check)