Are you mechanically inclined?
Do you think you can handle pulling the carbs?
Of course you can!!
More than likely the carbs and internal parts need cleaned. Maybe the fuel tank & petcock also. Have you taken a look inside the tank to see it's condition?
The Seafoam was an excellent place to start. The carb cleaner...maybe not.
Some carb cleaners can have an adverse reaction to plastic parts in the petcock & carbs.
A good carb cleaning seems to be what you need.
Also, did you try changing the plugs at all?
What about the air filters? Are they clean?
Did the smoke smell like fuel, as in a flooded condition?
Oh, and welcome to the forum
AKA: Tim & 'The Adventure Cycle' VROC #24567, NEVROC, SteelCity VROC
"When life throws you curves,
Aim for the apex."