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Discussion Starter #1
This bike is killing me, with chasing problems, this time it started with it running on time on one cylinder after I had cleaned the carbs bench sync. I had it running near perfect after the first time I cleaned it but I stalled it towards the end of first ride and it hasn't been right since. I don't recall hearing a pop but I checked for a vacuum leak using carb cleaner around the boots, and replaced those.
Still on one cylinder so I started playing with the sync while it was running, after back the screw almost all the way out before any change but after I re cleaned and sync the carb this time as shown (last time I leveled the butterflies at full) it's now revs up and good back to idle but I still can't open the chock even half way.

The only thing I can think of is that the rubber boots from the air box to the carbs being dry rotted and cracked is letting in too much air, I unfortunately can't find the parts new without them being 20+ apiece, and I'm also concerned that fixing that will only show more problems that needs fixing.
 

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Take some carb cleaner and spray the boot area while the engine is running. If the engine rev's up, then the boots are probably leaking or you have vacuum coming in from somewhere.

I had an old 1984 Honda V65 Magna. I had a hard time trying to find the boots since the originals were completely cracked and falling apart. I ended up finding a radiator hose that had an ID the same as the boots and cut to the right length it to use as boots. Worked perfectly and never had an issue for 2 years until I sold it. I included a pic as a reference. Not sure I actually took any pics of it..
 

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Discussion Starter #3
I would try checking for vacuum like that but with it reving up and down so much
I don't think it would be conclusive
 
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