for some reason while sprinting on my big ring, and somewhere in the middle on the rear (so not cross chaining) the chain will drop off, I can't figure it out for the life of me, there is no chain rub on the derailleur.

I am tossing the bike from side to side rather violently, but thats me sprinting, never had this problem with my MTB before.

Could it possibly be the low end Truvativ Touro cranks/chainrings flexing?

Thoughts, opinions?

TIA
-jacob

ps i did in fact do a search, but everything I found had to do with problems while shifting