Force while moving

A thought occurred to me that there must be some force acting on moving bodies.

For example:

    1) How can one easily balance a two wheeler when moving, while it  is difficult to balance while it is not moving?
    2)  If we generate enough velocity we can fly...where are a steady object cannot float in air.
       People talk of Bernoulli principle for flights. However, how can one think that air wants to or needs to travel faster to reach other end? 
   
  Now, we know that there is a centrifugal force corresponding to angular velocity. However, how can we not imagine that there is a similar force for straight line motion?

  However this is just a thought....need to work more on this