My car dont move

My car dont move and have rigidbody 1500 and this script

 #pragma strict
 var wheelFL : WheelCollider;
 var wheelFR : WheelCollider;
 var wheelRL : WheelCollider;
 var wheelRR : WheelCollider;
 var maxTorque : float = 50;
 var Speed = 10;
 function Start () {
  
 }
  
 function Update ()
 {
 wheelFR.motorTorque * Input.GetAxis ("Vertical") * Speed;
 wheelFL.motorTorque * Input.GetAxis ("Vertical") * Speed;
  
 }