My '88 Sammy starts and runs great when it's cold.  When it's fully warmed up to operating temperature and press the accelerator it stalls out...  Its completely stock.  Only 29k original miles.  Even the original tires!  I've replaced the spark plugs, checked the coil and plug wires, o2 sensor.  Any suggestions out there?

Choke?

It's an electric choke I think.  IT appears to be operating correctly.  Valve is mostly closed when cold, all the way open when hot.