why smaller stars rotate faster than bigger ones?

Question

anonymous · Answer

The magnetic field of a star interacts with the stellar wind. As the wind moves away from the star its rate of angular velocity slows. The magnetic field of the star interacts with the wind, which applies a drag to the stellar rotation. As a result, angular momentum is transferred from the star to the wind, and over time this gradually slows the star's rate of rotation.

Yield larger radius would produce greater drag intrinsically.

anonymous · Answer

IMHO  in my humble opinion
I am just extrapolating the theory, not my expert field of knowledge.

anonymous · Answer

http://en.wikipedia.org/wiki/Stellar_rotation

anonymous · Answer

Maybe because smaller stars have a lower moment of inertia