diff --git a/Examples/BB2B/BB2B.cs b/Examples/BB2B/BB2B.cs
index 815fdb1..4f1c3cf 100644
--- a/Examples/BB2B/BB2B.cs
+++ b/Examples/BB2B/BB2B.cs
@@ -11,6 +11,7 @@ namespace RoboidControl {
 
         public BB2B(Participant owner) : base(owner) {
             this.name = "BB2B";
+            this.SetMotors(new Motor(this), new Motor(this));
             this.SetDriveDimensions(0.064f, 0.128f);
 
             // Is has a touch sensor at the front left of the roboid
diff --git a/Unity/DifferentialDrive.cs b/Unity/DifferentialDrive.cs
index 91c0883..a0e4b99 100644
--- a/Unity/DifferentialDrive.cs
+++ b/Unity/DifferentialDrive.cs
@@ -52,6 +52,14 @@ namespace RoboidControl.Unity {
             if (coreDrive.wheelRadius <= 0) // || coreDrive.wheelSeparation <= 0)
                 return;
 
+            // Destroy any (generic) thing with the same id
+            if (leftWheel == null) {
+                Thing[] things = FindObjectsOfType<Thing>();
+                foreach (Thing thing in things) {
+                    if (thing.core.id == coreDrive.leftWheel.id)
+                        Destroy(thing.gameObject);
+                }
+            }
             if (leftWheel == null && coreDrive.leftWheel != null)
                 leftWheel = Wheel.Create(this.transform, coreDrive.leftWheel.id);
             if (leftWheel != null) {
@@ -61,6 +69,14 @@ namespace RoboidControl.Unity {
                 // leftWheelCollider.center = new Vector3(-coreDrive.wheelSeparation / 2, 0, 0);
             }
 
+            // Destroy any (generic) thing with the same id
+            if (rightWheel == null) {
+                Thing[] things = FindObjectsOfType<Thing>();
+                foreach (Thing thing in things) {
+                    if (thing.core.id == coreDrive.rightWheel.id)
+                        Destroy(thing.gameObject);
+                }
+            }
             if (rightWheel == null && coreDrive.rightWheel != null)
                 rightWheel = Wheel.Create(this.transform, coreDrive.rightWheel.id);
             if (rightWheel != null) {
diff --git a/Unity/Wheel.cs b/Unity/Wheel.cs
index d68b9b6..e40891d 100644
--- a/Unity/Wheel.cs
+++ b/Unity/Wheel.cs
@@ -23,14 +23,6 @@ namespace RoboidControl.Unity {
                 GameObject gameObj = new(core.name);
                 Wheel component = gameObj.AddComponent<Wheel>();
                 component.Init(core);
-                // component.wheelCollider = gameObj.AddComponent<WheelCollider>();
-                // component.wheelCollider.mass = 0.1f;
-                // component.wheelCollider.suspensionDistance = 0.01f;
-                // component.wheelCollider.suspensionSpring = new JointSpring {
-                //     spring = 100f, // Very high spring value to make it rigid
-                //     damper = 10f,    // Low damping (could be adjusted for slight 'bounciness')
-                //     targetPosition = 0.5f // Neutral position (middle of the suspension travel)
-                // };
                 Debug.Log("Create " + core.name);
                 return component;
             }
@@ -61,14 +53,6 @@ namespace RoboidControl.Unity {
                 SphereCollider collider = gameObj.AddComponent<SphereCollider>();
                 collider.radius = 0.00001f;
                 collider.material = slidingWheel;
-                // component.wheelCollider = gameObj.AddComponent<WheelCollider>();
-                // component.wheelCollider.mass = 0.1f;
-                // component.wheelCollider.suspensionDistance = 0.01f;
-                // component.wheelCollider.suspensionSpring = new JointSpring {
-                //     spring = 100f, // Very high spring value to make it rigid
-                //     damper = 10f,    // Low damping (could be adjusted for slight 'bounciness')
-                //     targetPosition = 0.5f // Neutral position (middle of the suspension travel)
-                // };
                 Debug.Log("Create placeholder Wheel ");
                 return component;
             }