Hello there! Welcome to the world of pokémon! My name is Oak! People call me the pokémon Prof! This world is inhabited by creatures called pokémon! For some people, pokémon are pets. Others use them for fights. Myself...I study pokémon as a profession.
Pidgey, a small bird Pokemon, and the first evolution of Pidgeott can be caught at the very beginning of all generation one Pokemon games.
Despite its small size, and relative weakness, it can learn the move Hm 02. Hm 02 is the move fly which allow the trainer to travel to any town in the Kanto region in which said trainer has visited the Pokemon Center, after receiving the Thunder Badge from Lt. Surge. But, is jumping onto the back of this tiny bird Pokemon safe. I would say no. According to my research the average force required to break a birds wishbone is 620N. The average human has a mass of 70kg and thus a 700N force due to the acceleration due to gravity. Thus, by jumping onto the back of a Pidgey or any of the bird Pokemon would result in the breaking of the poor things bones, and an immediate trip to the nearest Pokemon Center. Maybe try something a little stronger, Charizard or Drangonite may be of some use now.