A little update on the jetting.
I’m up to 35 pilot and 300 main jet. I still get a little pinging sometimes when I’m on the needle jet when cruising at 50-55 mph for a while. It also pings when I chop the throttle after at high rpm. At this point I think that my needle is too lean. I have a 5e75 needle right now and I think I will be switching to 4j13, which is what the factory carb had. According to what I found it is a little richer at the beginning of the needle and hopefully this will solve my problems. My other option is to use a higher octane fuel than what I’m using now which is 93 octane.

5E75 needle looks to be richer pretty much through the range compared to 4J13.

specs say you have an N-8 needle jet and CT came with an O-6 which is considerably richer... 

ID on N-8 = 2.590mm
ID on O-6 = 2.630mm which is 0.04mm larger than N-8

5E75 needle is shown as 2.43mm diameter at start of taper.
4J13 needle shows 2.512mm diameter at start of taper

Tapers can and probably do start at different distances down the needle so you need to look at that. 

Someplace I have a very complicated spreadsheet that shows and compares the flow area for different combos of needles and needle jets but you can get a good idea having the needles side by side and with a caliper.  (Even better is laying the needles side by side on one of those old fashioned overhead projectors we had in school and comparing the magnified needle shadows on a screen or wall...  (and yes, I used to do this when tuning and trying to select a different/better needle to do what I wanted.)

Anyway, be careful with the 4J13 as it looks to be leaner at start of taper. 

P.S.  "Pinging" when letting off the throttle might be something else entirely...  detonation-type pinging generally tends to happen under load.

You are right, I am not sure why but I was thinking backwards about it! Back to the drawing board!

I think i may stick with playing with needle clip positions with combinations of even larger on the main jets.

are you referring to the dragonfly75 excel sheet calculator? I think I might invest into that and see if that helps. My other thought was to weld a bung on the expansion chamber and put an o2 sensor and see what kind of readings I get. According to some research I've done some people have decent luck putting those on 2 strokes. 

It sounds like pinging, but it might be something related to the expansion chamber, combustion and gas dynamics there. I am not sure to be honest, this is my first 2 stroke that has more power than a chain saw or a moped.

Reading back to the start & bogging on full throttle. Is that sorted now. Bogging could be taken two ways in meaning. If it's way too lean I'll just gasp & pretty much stop running. If it's way to right it'll peak out & blubber--4 stroking & not get past those revs but will stay running. So exhaust is totally  unrestricted. I got bad reed flutter in a highly modified motor at about half revs at the point where the exhaust started to do its chamber thing & blubbering like over rich on the needle but couldn't cure it. Then someone far smarter than me cane up with the answer, so I doubled the reeds & fixed it on the spot. Just saying & might not be helpfull.

photos.app.goo.gl/nPoeKxviCMbSYywF6 My restricted exhaust. On my RMX250.