Rigidbody.maxAngularVelocity  

var maxAngularVelocity : float

Description

The maximimum angular velocity of the rigidbody. (Default 7) range { 0, infinity }

The angular velocity of rigidbodies is clamped to maxAngularVelocity to avoid numerical instability with fast rotating bodies. Because this may prevent intentional fast rotations on objects such as wheels, you can override this value per rigidbody.

rigidbody.maxAngularVelocity = 10;

using UnityEngine;
using System.Collections;

public class example : MonoBehaviour {
    void Example() {
        rigidbody.maxAngularVelocity = 10;
    }
}

import UnityEngine
import System.Collections

class example(MonoBehaviour):

    def Example():
        rigidbody.maxAngularVelocity = 10