Funny that: my other half rung me yesterday with exactly the same problem. As she was several hundred km from home she called the assistance (we get our money's worth from our expensive insurance).
She's not the only one, read the same story on the German DR forum. Seems a common fault.
It's not electrical, but fuel starvation, as indicated by the fact that the bike starts again shortly afterwards.
Things to check:
Fuel filler cap, is it letting air in?
Fuel filter in the carb. To get to it, pull the fuel hose off the carb. You can see a small pieco of plastic on top of the inlet pipe. Lever and pull it out carefully. It's a tiny filter that easily clogs. If this filter is missing the dirt could be in the needls valve.
Fuel filter in the tank. Although, it's reasonably large and visible with a torch through the filler hole, I think.
Other causes are possible, but less likely, like Steve's hint at electrical problems, bad connections, etc.
Good luck, shouldn't be hard to find.
Salut from Southern France, the bikers' paradise,