HiOSilver...........WOW, that is definitely an eye opener, I have never heard, at least on this board, anything closely resembling your experience.
I can theorize the following taking place:
1) You did have some gasoline ignite in the vicinity of your throttle body.
2) The instantaneous force of the ignition and the gasses expanding blew the TB from it's attachment fixture.
You mention that upon your return home, the Twinmax check and the bike idle were both OK, so how did the above happened? (I see that you live in Arizona)
1) You could have had a backfire from the combustion chamber back through the intake valve. That means that the valve didn't close properly, at least during that first start. Maybe it hung uo? or had a piece of carbon lodged in the seat that got also blown out after the incident, but I find this scenario hard to believe.
2) You could have a leaking injector, further exarcerbated by the fact that you had just ridden the bike (hot bike), you live in Arizona (hot weather). The injector in question, allowed some of the fuel in the pressurized line (~ 42 psi) to leak and either remain in the TB area or even puddle in the back of the intake valve (if the valve was closed) or even puddle in the combustion chamber (if the valve was open)
Upon start up this fuel was subsquently ignited and expanded very raidly causing what you experienced......
In my mind the above explanation is the most likely scenario. I would sugest the following:
1) In warranty - Take the bike to the dealer, explain what happened and see what they come up with, (don't offer any sugestions, nor mention this response) that way you can get a perspective on A) the dealer's interest in helping you and B) the knowledge base they have in-house.
2) Out of warranty and you like to tinker with the bike - Take the bike for a ride, return home and let it sit in the sun for about 20 minutes (replicate the condition of the incident) and propceed to remove the injector from it's mounting, still connected to the fuel line. Let it hang and observe, for a few minutes to see if the fuel leaks out from the injector bottom. If so you have your answer........
3) Out of warranty, but you don't fool much with the mechanical end. Have both injectors removed, identify their possitions and have them tested. The test will reveal if you have a leaker and will also check for delivery amount and spray pattern, That should also provide the answer.
In closing, I like to mention a similar instance with the CIS or K-Jetronic injeted Prorsche 911's of 1974 to 1983 vintage that had the propensity to have fuel present in their airbox which routinely ignited and didn't have a way to scape resulting in blowing a hole in the ~ $250 airbox!!!! They came out with a kit that installed a pop off valve for when this phenomena took place and of course to save buying an airbox everytime it happened...
I don't have any other explanation for your experience and I would say that you were very lucky that no other damage took place. I will also mention that it is unlikely that the engineers designed the TB to dislodge the way it dd....that would have required far too much forward thinking.
I hope this helps............
And to MikeCam....thank you for your vote of confidence. I'm touched that you include me with such elite company......
I managed to coax the throttle body just slightly back into the rubber retaining ring on the cyclinder and it was enough to get me home. It ran just fine all the way home (about 10 miles). When I got home I re-installed the throttle body correctly and then tried to figure out what caused it to backfire so violently. I attached my Twinmax and found everything perfectly balanced at maximum sensitivity.
I had ridden about 15 miles, parked at a local sporting goods store and left it for about 20 minutes. When I got out of the store and this happened the engine was still warm, but not hot.
I've stopped and started it several times now and it is behaving normally. Would you worry about it or write it off as a random occurance?
Like I needed and excuse!