Ball Python Dropped dead, any ideas?

[Vypyrz]

...or the ride home was too stressful.

I also wonder since it was a motorcycle ride what kind of temps where in the compartment with the snake.

I'm not a breeder, but I am a biker, and I would say it was probably a combination of heat stress and the added stress caused by the excessive vibrations from the bike. Most saddle bags/storage compartments are designed to keep their contents dry in the rain, so I doubt that there would be very much, if any, ventilation.