I thought of mentioning the pick up sensor as well.
I haven't had a problem with mine but from what i've read the bike would have to cool a bit before it would run again. Your description makes it sound like it will start moments after it dies. That would make me think the tip over valve or gas cap vent.
The pick up sensor is under the right hand crank cover.
Two screws and unplug is about it. There is an air gap to check during re installation.
Here is a picture that shows the sensor pretty well.
Stan
[ This message was edited by: SWare on 2005-10-07 19:10 ]