As one who wore Nomex green nearly every day for many years, I'm curious why you want it for motorcycling.
All Nomex does is slow down tissue burns. It doesn't burn by itself, but instead chars when it gets to about 698 degrees F.
It essentially buys you a little time to escape a fire, but you can still cook inside it.
It provides no other protection, so if you're looking to avoid road rash, broken bones, blunt force trauma, cerebral avulsion, etc, a military flight suit won't do it. If you ride behind a fuel tanker that ruptures in front of you and ignites, you might be ok for a little while.