RacingSystem.cs(28,96): error CS0201: Only assignment, call, increment, decrement, and new object expressions can be used as a statement

Attempting to make a racer go around corners. (they collide with an arrow and then get the rotation of the arrow object so they go around the corner.) RacingSystem.cs(28,96): error CS0201: Only assignment, call, increment, decrement, and new object expressions can be used as a statement (ignor raycast, this works for my racer potitioning.)

 using UnityEngine;
 using System.Collections;
 
 public class RacingSystem : MonoBehaviour {
 
 
     //checkpoint handler
     public GameObject Checkpoint;
 
 
     // RacerStats
     public float Speed = 1;
     public float MaxSpeed = 12;
     public float acceleration = 2;
     public float TopspeedTime = 7;
     public float Turnspeed =  6f;
     public float RacerPotision = 0;
     public float TrickActive = 0;
     public float DriftActive = 0;
 
     public GameObject RacerPotition;
     public GameObject ThisRacer;
 
 
     public  void OnCollision(Collision collision)
     {
         if (collision.gameObject.name == "Turn") {
             ThisRacer.transform.rotation == collision.gameObject.transform.rotation;
             // when a Racer detects a corner, the racerrs rotation becomes that of the corner and turns.
             // turnsped is for smoothing.
     }
 
     }
 
 
     public void Update (){
 //-----------------------------------------------------------------------------------------
         if(Speed > MaxSpeed){
             Speed == MaxSpeed}// Limit Topspeed.
             // Accelleration Amination.
 
             // Tunrning The Racer.
 
 //-----------------------------------------------------------------------------------------
 
     }
 
 
 
 
 // Racer Position
     void HitByRay () {
         // Get Raycast Number to determan Position of Racer.
         Debug.Log ("Hit by RacerLine Raycast");
         RacerPotision == RacePotiotionRayCast.PotiosionCalculator;
     }
 
 }