Adjust the idle RPM at 1100 RPM, not less.
When the engine dies at low RPM the piston will stop at TDC. The low inertia of the crankshaft is unable to overcome the compression.
You can check the device thats put extra fuel in the carb when the trottle is closed ( can't remember the name) It's fitted left from the idle mixture screw and has a 3 screw cover. The transient enrichment valve.This can be dirty/stuck or the rubber diafragm punctured.
When you open the front (exhaust) valve adjustment cover you can see how the decrompression solenoid acts on the exhaust valve rocker. Bit difficult to explain.
On my engine (1993) I have installed an electrical device that operates the solenoid also when switching off the engine, not required for engines later than 1996 as the starter gears were changed after that date.
My advice to check the general mass connector behind the LH sidecover still stands and I might add check the sidestand springs, if they are weak the sidestand switch may interupt the ignition momentaraly and the engine dies.
Keep us posted, very interesting in what you find.
Greetz
Kropatchek