Need help with Torque and Angular Velocity.

So I have been working on a 3D platformer with a fixed camera angle. I have already setup the camera, the player and the first scene. I made some basic movement code for my player in C#. Here it is:

Code (CSharp):

1. using UnityEngine;
2. using System.Collections;
3.  
4. public class Movement : MonoBehaviour {
5.     public float rotationspeed = 100.0f;
6.     public float maxrot;
7.  
8.     // Update is called once per frame
9.     void Update () {
10.         Rigidbody rb = GetComponent<Rigidbody> ();
11.         rb.maxAngularVelocity = maxrot;
12.         var rotation = Input.GetAxis ("Horizontal") * rotationspeed;
13.         rb.AddRelativeTorque(Vector3.back * rotation);
14.     }
15. }

Now this code is good and all, but I have 1 slight problem with it. The ball/player takes forever to change direction. If I'm going full speed one way, and then I change direction. He slows down for about 3 seconds, turns, then speeds up for about 3 seconds. Any idea on how to speed this up. Also if you could help with an accelartion code, that would be very helpful. I want the player/ball to slight increase in speed as time goes on.

 

You could put a PhysicsMaterial on it with bigger friction, however this may slow down acceleration.