When we stayed at a Mariott (I assume the rules are the same for all Mariotts) last winter we had the bellmen lock our kids bikes in the bell closet and we brought our mountain bikes, dirt, grease and everything to the room. Through the lobby and up the elevator daily. No one seemed to mind, we did have to resist the urge to ride over the golf course greens, I don't think that would have gone over very well.
Enjoy your trip and good luck on the ride!