User blog comment:JAlbor/Wikia at E3 2012/@comment-24.62.196.37-20120527201301/@comment-4772788-20120527202251

Yeah, The only reason Odahving let you ride him ONCE is because it was his way of staying alive (it was either that or remain trapped in dragonsreach). Remember that dragons are proud creatures and the closest you could get to convincing them to let you ride them would be the 5 seconds you are on the dragon while you blugeon it to death with a war hammer...