When you dig into the carb again ,  pull out the slide ,look down into it two things you should look for is that there should be two small holes in the bottom , that you can look through (Vacuum ports) and that the brass plate has a dimple very near the needle that should protrude downward. If you don't see these,  the plate is positioned wrong (180 degrees out- blocking the ports) or upside down,( the dimple protruding upward toward you.) You should also be sure that the tongue on the outside of the rubber diaphragm is fitted in the slot , and that you seat the rib on the outside edge in the slot in the carb body before replacing the spring and top cap.

Here is what it looked like when I took it apart first. Dimple up and partially blocked holes.

Well it's still happening. Lol. Maybe valves off or timing? I'm guessing valves, I say that because they are noisy. A lot noisier than I remember my other savage. Did a quick video. https://youtu.be/a3LuFRRayb4

I'm done with the supertrapp, already trashed it, wasn't in the best of condition anyway, tons of rusty metal falling out of it from the inside, it was junk. New muffler is much better. I will probably be getting a Harley muffler this Saturday, local guy posted on craigslist for $10, he's got 2. Anyway, carb specs, main jet 155, pilot 52.5, mixture screw is currently at 2 3/4, I'll dumb it down to what you suggested batman but think it'll make it worse. I'm going to dive into the valves tomorrow when I can. I think they're a bit off which is helping with this issue. I tested the coil and it's right in the middle of the specs, same with stator, pickup coil was on the lower end of the spec but within spec ( possible issue? ). I did ride it and still getting the issue. I did read valves or timing could be causing these issues. There's no intake leaks around the rubber manifold but I'll double check that, could be something going on there. Thankfully I've become very quick at disassembly, lol, I'd say 50 times I've had the thing  apart. I got 2 savages recently, made one, used parts from 3, traded parts for what I needed. 2001 frame forks wheels etc and electronics mostly, 96 bottom end, 87 head and valve cover. I'll get it for sure. Thanks for the help, definitely need it and it's helping me!

Was quick to put this together, valves looked good but wish I would of lapped them before I slapped the head on. I usually do but I've been bikeless for a few months and it sucks. I'll put them on the higher side of the specs, I know Suzukis like to breathe. Had a gs850 that did well on the higher side of vavle clearance. I have the original airbox and filter. Going to dig into the valves before it rains.

The decomp cam will hit the rocker when the lobes or rocker are worn.

Guess it's what I get for cutting corners to get it done fast...sigh, it figures because the time I choose not to measure things and get in depth with a build things are out of wack. First and last time I do that.