I don't really know, but I'd guess maybe the air filter (into the throttle bodies), or maybe the plugs. Just a thought.
It happened to me the first time a couple of weeks ago. I've never had trouble starting right after washing, and I normally ride around a bit to blow it dry. This time I didn't & rode it right back into the garage; a couple of days later it was a PITA to get it started but eventually it caught.