Why are Asians generally more intelligent than black people ?

Because black people are inferior. 

And what is your measure of intelligence?  Generally speaking, race is not a valid differentiator so you are engaging in racist rhetoric.

Why do you think you are intelligent enough to understand why?

They're not.  They're just raised in a different culture and haven't had the same strikes against them.

There's no group of people on earth that is innately more intelligent then other groups.

Black people are too arrogant to move forward into the modern world. Due to their stupidity as well as narcissism they want the world handed to them on a plate.