I got one for the gurus,

2009 with 5595 KM's
Free flowing petcock
K&N cone filter
Dyna pipe
150 main
1/2 spacer
55 pilot (?)

The main problem is my engine is cutting out when the throttle is closed.

With a 52.5 pilot at 2.5 turns it starts and idles fine but revs like turd. I get a very weird choking (sputtery) sound at 1/8 throttle and backfires through the air filter. Once past the pilot jet it revs fine, but getting past the "choke" is laborious. So that being said I thought *lean* and moved up to a 55 pilot

With a 55 pilot at 1 turn it starts, idles and revs great. However, when the throttle is released or let off completely idle drops and the engine cuts out. I can blip the throttle a bit in order to keep it from stumbling to low and then the idle stabilizes.

I've cleaned the carb, as well as the TEV (tried my luck with a washer/spacer), checked the float (which was a bit low of spec.), new sparky, fresh gas, and sealed the pipe. Maybe an air leak or cut the TEV spring?

Anyone have ideas?

Sorry, when I said "a bit low of spec" I meant the float height not the fuel level. I adjusted the float from 25mm to 27.5 (off of the gasket). I will give it a shot, bump back down to a 52.5 and see if it makes a difference.

JOG- How far should it be from the seam?

Not above it, IIRC, right at it. I doubt being 1/8" below is a problem.
Bet someone here knows Egzaklee.

I don't think we've ever determined what causes shutoff at throttle chop.
Normally we just say increase the idle speed.

TEV is meant to prevent backfire at shift with extra air throttle chop for shift.  
And playing with the spring can get you into trouble really quick cause we are way to heavy handed.
Adding a washer is the safest route, but maybe the opposite way is the way you need to go.
Don't shorten it unless you got a backup.

If it's dumping gas in the intake it could be in the oil. Snotta good thing.

I have checked it with clear hose through out the whole process and it has never gone above the seam of the bowl. It was actually 1/8" under the seam this last time which is the highest its been so far. No fuel in the oil that I can see or smell. It does correlate with what batman is talking about though it's sucking fuel in from somewhere at high vacuum.

Did you replace the main jet?you should check to see that you placed the brass washer that fits between it and the needle jet body (the cylinder with all the tiny holes in it)If not the jet can fall the thickness of the washer and that could dump extra gas in the carb as well, causing the same symptoms .the washer fits around the threads on the main jet and fits up inside the carb body.It gets missed sometimes because it tends to stick to the old jet and take on the same color as the jet.