Bike Dies Opening Throttle If It Runs At All

Brief rundown: '79 KZ750 twin, bought 3 years ago from a guy who had a sunk float in it and didn't repair it. Fought this thing for 3 years to get it running, cleaning the carbs time and time again and getting only one cylinder to fire at a time. Gave up working on it for a year out of maddening frustration.

Came back to it this year, and have done most everything to the bike: new coil, new points and condensor, new spark plugs, rebuilt carbs, new petcock, new battery. All set per the manual. Still would not run, not even so much as a pop. A week or two ago, decided to jump a wire from battery positive to coil for hahas. Got the bike to run, one cylinder backfired something fierce, had trouble revving at all, had to go slow to make it do anything. Shut it off at several points in the day, and it restarted first kick.

A day or two later, I took the carbs off to synchronize them, assuming that's the reason one cylinder was backfiring. Put it all back together, and no pops. Now the points have a weak spark again, even with the jumper that had given it a good thick spark and made it run. There is all proper connectors on it, going to a brand new switch. And yes, the switch was on during testing.

Bypassed the switch, no change. Hooked up the battery charger, slightly better spark, even though the battery had been charged overnight.

I am completely out of ideas, I have tried everything on here that I have read. I am beyond frustrated about wasting 3 years on this junk and havent gotten to ride it yet.

I would love for some new suggestions, anything at all. I would love to be able to ride this thing finally.

Thanks,

John

There should be no spark at the points. Bad condencers. You need a new battery at this point. Valves adjusted? Hopefully when you get it running you'll change your mind about it being "cursed."
Steve

Valves have not been touched. The condenser and battery are new, I can't see why they would have gone bad already. Also, why would there not be spark at the points? When it was running, there was a nice big spark between them as it would open, isn't that supposed to happen?

Valves have not been touched. The condenser and battery are new, I can't see why they would have gone bad already. Also, why would there not be spark at the points? When it was running, there was a nice big spark between them as it would open, isn't that supposed to happen?

*Edit* UPDATE: I have somehow managed to slightly bend the kickstart shaft enough that i can no longer get a good kick, so at this point my ship has sunk. This is about as far as I can run on hatred and frustration.

The condensers prevent sparking at the points and allow the coils to build up a charge. Also to prevent pitting of the points. No electric start? Valves need to be in spec or the bike won't run for SHT.
Steve

I tried to reply several days ago, guess it didn't post. I had taken the side cover off, the flywheel was backed out probably close to an inch. Cleaned all the oil off the bolt and the hole, loctited and torqued. Still slips, and the clutch on it is torqued as well. Can't get any voltage through the coil at all from that switch, so I bought another, still a dinky spark. What is the issue here? I am truly lost. I had it so close, and now I lost my spark again.

You have to go through your wiring harness and clean all the connectors with De-ox-it spray
A lot of voltage drop is a result of a bad electric connection.
A hidden power consumer in the wiring harness can make you a bad day.

I have completely bypassed the wiring harness, using new wires and connectors to a switch that solely supplies power to the coil. That is how I initially got the bike running, but now it's being finnicky again.