Keihin CV34 Tuning and Balancing after Rebuild. May Have Broken Air Fuel Needle

REBUILT CV-34 with another carb body to replace the one with needle damage hoping it would solve the cold 3rd exhaust pipe problem. On starting (ez to fire up!) I could tell only 3 cylinders were firing. Idled under 1k with choke off.  3rd pipe cold.

Blasted through all ports and transferred over all new parts from the 2015 rebuild. I checked valve clearances after the machine shop returned it to me. If not in the carb, it has to be in that valve body.  When it started up last fall Aug 2020 it rev'd up really high before I could shut it off and adjust the idle.  I'm hoping none bent; it sounded mechanically maxxed, but wasn't topped out on the tach.  Thoughts? Bust open and run all the checks again?  Clymber lost in divorce shuffle...

Float fuel level is just below the mount lip of the bowl, not a nickel width below that, so maybe a tad high?  Spark confirmed. Old plug black and wet with fuel. Cold pipe still on fire up.

Edit.
Checked all floats, needs re-done.

Petcock not stopping fuel flow in the On position, behaves like it is in Prime.

Flooded cylinder and bad oil I'm assuming. 

I drove it out from KC to Denver on a trailer. Is it best to drain the carbs first? Time to go back thru... maybe see about alternative petcocks.  Already rebuilt once.

Stock emissions piping removed years ago mid rebuild.  I fixed the petcock, maybe the rubber slipped in there? No more pissing gas. 

Re-balanced all the floats.. left two were off - a lil low and a lil high.

I have compression, blasted my thumb off.  Rotated the 17mm ignition bolt counter-clockwise and viewed the valves moving in and out, piston up and down. 

New sparkplug looks unfired so far. Pipe got slightly warm with high rev.  Hangs above 3k for a sec. Sounds normal bad, now have some backfiring it sounds like. Feel so close... damn it.

Here is the video, noisy pinging inside, seems new.  Time to disassemble the top again? Chain tensioner issue?

The smaller main may have been for jurisdictions with stricter emissions standards,

Any updates? I'm having similar issues...

That engine noise sounds bad.  Time to open the valve cover for a inspection. I'd check the cam chain tensioner too.  And realize that you have to release the tensioner spring and wedge before installing the valve cover otherwise you will over tension the cam chain when the cover goes on since there is a rub block in the cover which presses down.

+1 on the cam chain tensioner. Last year I had my manual tensioner back way way out - I probably did not tighten the lock nut sufficiently - and the engine sounded like yours. Possibly worse. Like an ancient farm tractor  with a rotten muffler. I was sure it was terminal. 

Also. Cant see the valve cover in the video but did you block off those emissions ports/outlets when you removed all that stuff?