Regarding the sudden power loss, I'm wondering you were getting close to needing reserve and it gulped some air for a moment or maybe a little piece of trash got caught in the main jet and then broke loose.  About the noise, not too sure.  A small hole in the top of the piston might do that but I figure you'd have a few more symptoms to go with it.  Common sense says to look for simpler things, especially so since it's a new bike.   A muffler starting to come loose at the header joint might give you a little noise that might accentuate the bike's normal engine noise.  Also, when something strange happens to our bikes, we sometimes become more attuned to noises and discover sounds we really didn't hear before cause we are paying more attention.  

How long were you at "full grin"?

Is this "thump" more like a knock?

Possible reason for the sudden silence is the petcock.  If the vac line is cracked, loose, leaking, at WOT the vacuume is low.  With a leak the petcock will shut off and you'll run out of gas with a full tank.

Possible reasons for "thump" as we all know, a puckered anus will improve your hearing.  Stock bikes are notoriously lean, prolonged run at "full grin" may burn a piston depending on how bad it is.

Just one note of caution with running it w/o the fill plug, don't stand in front of it.  There's plenty of air moving in and out of the crankcase due to the piston going up and down.  There's also a lot of oil being thrown around.  Some of it will shoot out.

I doubt that you have a hole in your piston.

And with the filler open, normal engine noise will be louder.  Since you most likely haven't heard the caucaphony yet, don't be extremely alarmed.

Note, He said SMOKE, not an oil mist, which can happen with all the air moving back & forth.

Scuffed piston, just one person's ignorant guess which is all we can make at this stage of things.  This from the "averaged" answer for the "mysterious thump noises that leave the bike running".

Solution -- first do not tell the dealership any details about what you were doing -- just clam up.   Don't lie to them, just shut up on the details.

Take it in for warranty service.  Make sure you have them check the fluids and such to verify the oil level is correct in the sight glass, etc.

(you did make sure you have the right amount of oil, right?)

Document everything -- you are liable to have some sort of dispute with them so disputes go to the one with the best records, generally speaking.

Good luck -- going 90 mph on a thumper is stretching things a bit that early in the bike's life.  Still, you were past the break in period and still under warranty, so it is their issue to fix.