Nothing indicates to me a starter problem yet. I think it would help to cover the ride a lot better where the bike "Hissed, died, rear wheel locked up for 2 seconds....then restarted".
A few questions come to mind:
1. Is there any oil in the engine?
2. With the bike in second or third gear, will the rear wheel turn when you try to bump [push] start the bike? If not, this may indicate a locked up engine. when the engine died on the road at 50+ MPH, there was enough momentum to break loose an engine that had seized up. The starter won't have that kind of torque available.
3. My opinion is that you will need to determine that the engine is either stuck or free before much else can be determined or other trouble shooting methods used.
Welcome to the forum, there is a lot of help here, and let's hope this is simple and painless!
“many a trip continues long after movement in time and space have ceased”- Steinbeck, [I]"Travels with Charlie"
[FONT="Century Gothic"][I]Sometimes your only available transportation is a leap of faith[/I] [/FONT]