Quick throttle bogg down

After full carb rebuilds my bike does run now.  Idles pretty good at 1,100 rpm.  Getting occasional popping that I have not tracked down but spraying carb cleaner around the intake boots shows no leaks. The biggest issue right now is rapid throttle advance just boggs down. I started the air mixture screws at 1.5 turns out.  And I’ve tried fewer turns and more turns with no improvements    Looking for suggested next steps

Since You have a 1980, you should have the accel pump assy on #2 float bowl. Are you still using the original carbs? On these types accel pump function is mandatory or you will always have that "flat spot".

I started looking into the accelerator pump today.  Attaching 2 photos.  I can blow air from inside the carb bowl and it does come out the hole (other picture with red arrow), but I can't seem to blow air the other way.  Is this a one-way valve of sorts.  Since I can blow air from inside the carb bowl to the accl. pump I filled the carb bowl with fuel and it barely drips out that hole.  Shouldn't it just continue to run steady until the carb bowl is empty?

The "out" from the accel pump is normally under pressure generated by the diaphram. The passage is small so that the pressurised fuel "atomises" rather than being delivered as a "glop"

I can not tell from your pics, and I think in 80 stock made use of both, but does your set have both of the diaphragms or just the one on the pump? If it uses both the triangle shaped ones purpose is to not allow the pump to squirt fuel unless there is vacuum present (engine running). If there is a tear in the 3 sided diaphragm no fuel will be squirted by the pump into the carb. If on the other hand your set only makes use of the pump it should squirt fuel into the carb throat when ever you pull the throttle, as long as there is fuel in the bowl.

Pics attached of one with both and one with only the pump.

I don’t have the vacuum portion.  Just the one on the pump

As GD4 has been soo nice to show, that's the pieces that make-up the pump/#2 bowl. If You don't have the "sensor diaphragm" then that area/hole used by the that accessory is merely the fuel inlet for the pump diaphragm. Shown in blue marker, pretty straight forward. The bowl is cross-drilled to allow fuel to flow from Blue hole to Red hole with the singular ball bearing/spring and brass cap. I always pull the brass plug to access ball/spring. This allows me to clean better and check/clean the brass sleeve/seat for the ball bearing which is pressed in. A lot of crap can build-up in the lower sections of both cavities over the years and you can't clean what ya can't see. The accel pump diaphragm does two different things, Vacuums and Pressurizes. When throttle is pulled it pulls accel pump lever arm up forcing fuel into the labyrinth of bowl hoses/galleys and fuel delivery nozzles. You will note each bowl also has a ball bearing and brass weight. But each bowl also has a pressed-in brass ball seat. These, similar to a float needle/seat need to seal when throttle is released. If they don't or oring on nozzle is leaking between carb casting and bowl, you will get spotty fuel delivery from nozzles. If any leaking to pressure delivery you won't have vacuum to pull fuel from the bowl or lift the ball bearing in float bowl. This is also where a warped carb casting can come into play. Because the castings warp at the exact centerline note where the nozzle oring is!! Right in the centerline! A non-stock/thicker oring is needed in this case to compensate. Food for thought..                 

That’s great additional information. If that brass plug is pulled can it be reused or must it be replaced.  I haven’t seen that part of my carb rebuild kits. In my pictures above my plug looks more black so maybe it’s not brass, not sure. 

could the reason my fuel flows through to the accelerator pump be dirty passages there.  Or is slow flow ok as long as it’s flowing

LTDflyer1000 wrote:

That’s great additional information. If that brass plug is pulled can it be reused or must it be replaced.  I haven’t seen that part of my carb rebuild kits. In my pictures above my plug looks more black so maybe it’s not brass, not sure. 

could the reason my fuel flows through to the accelerator pump be dirty passages there.  Or is slow flow ok as long as it’s flowing

if you are referring to the pump "nozzle" the flow will be slow under atmospheric pressure, the nozzle hole is intentionally small to encourage atomisation of the fuel being pumped

That brass plug can absolutely be reused Flyer, just be mindful when soldering ya don't get any solder on the sides. I put them brass slugs on a metal punch bit to keep solder from corrupting the inner area where the spring sits. Don't want flowing solder to do more then it's job of just filling the hole you mad to remove. I use Flux paste to provide a good bonding after cleaning and soldering with a fully heated 25W soldering iron, just kiss/heat it enough to let the solder flow in this area. I use 60/40 solder with rosin core electrical solder, extra benefit of bonding. Aint't gotta be pretty but you want a sealing slug within the casting. Just re-set it flush to bowl casting tower. AND, DON'T use too big of drill bit when making the hole to pull, you'll wrap the spring up with the underlaying spring, destroying it! Wookie, nothing in this set-up is atomized fuel delivery. Just raw fuel dispersed from the 4 intake side nozzles.          

Thanks Clay, I would have expected it to create a spray - every day is a school day

Every Day is 101 classroom day Wookie!! I don't profess to know it all, only the crap i've experienced first hand i regard to, but that's OK. I have a thirst for continuous knowledge from my brothers of familiar. Once we say we know it ALL we become the unfortunate standard of those that are intolerant of opposing opinions and only dependent on self validation, figuring it's the ends to the means. That's just plum sad and can't argue against that personality type.