Flat track shape

[bigpoppa]

Why are flat tracks are only oval?
And how come they never go the opposite direction where they have to dangle off the right side?

 

[Amazon]

I would assume the nascar direction is because they heavily use the rear brake, meaning they need the right foot on the peg, not the sliding on the ground.

 

[TK4]

Why are flat tracks are only oval?
And how come they never go the opposite direction where they have to dangle off the right side?

They go clockwise in Australia - something to do with the rotation of the earth.

Watch a dirt track TT some time - there are L&Rs (and a jump).