Carb problems?

78 kz650c2. I can't open throttle without choke on, which is weird because about a week ago it started right up and ran fine.

I'm running 2 shorty mufflers from DCC, pod filters, 17.5 pilots, 112.5 mains, needle clip middle. New coils, points, and condenser. Ngkb7es plugs correctly gapped.

I'm definitely getting fuel and spark, and have good compression. Carbs were completely cleaned about a week and a half ago, new fuel filter, clean gas tank, fresh fuel.

Any suggestions?

The only thing that happened between a week ago when it started, and now, is that I made a tack weld without disconnecting the battery first. I thought this may have fried some electronics but they seem fine. Could this have caused a problem that I may be unaware of?

That is the classic symptoms of a clogged pilot jet system. You might have gotten some debris in the float bowls. Clean the jets mains and pilot and make sure all the small passages ways in the carb bodies are clean and clear.

Check for air/vacuum leaks on the carb holders or test ports.

Ok, so I pulled the carbs and cleaned all jets and orifices. Put back together and it wouldn't start.

Then upon turning the killswitch to off, I would heard a pop in the exhaust. I'm confused.

It also backfires every so often while I'm trying to start it. And the smell that comes out of the exhaust, right after the pop, is something I've never smelled before.

The starter engages for a split second as I turn the stop switch to off. That's when the pop occurs.

Check your battery, it's cables and grounding wires. Are you sure you put everything back together properly?

Checked my grounds and connections and they were ok. Started thinking that it was timing related so I adjusted my points again and after several kicks, it fired up and ran normally without the choke.