diff --git a/src/newgrf.cpp b/src/newgrf.cpp
index cda3f4d5d3..b0fb95c30f 100644
--- a/src/newgrf.cpp
+++ b/src/newgrf.cpp
@@ -9518,6 +9518,8 @@ static void FinaliseObjectsArray()
 			}
 		}
 	}
+
+	ObjectSpec::BindToClasses();
 }
 
 /**
diff --git a/src/newgrf_commons.cpp b/src/newgrf_commons.cpp
index eb8d3f8c40..071e4a108a 100644
--- a/src/newgrf_commons.cpp
+++ b/src/newgrf_commons.cpp
@@ -316,7 +316,6 @@ void ObjectOverrideManager::SetEntitySpec(ObjectSpec *spec)
 
 	/* Now that we know we can use the given id, copy the spec to its final destination. */
 	memcpy(&_object_specs[type], spec, sizeof(*spec));
-	ObjectClass::Assign(&_object_specs[type]);
 }
 
 /**
diff --git a/src/newgrf_object.cpp b/src/newgrf_object.cpp
index ccd46e2e92..c7c2c770ee 100644
--- a/src/newgrf_object.cpp
+++ b/src/newgrf_object.cpp
@@ -90,6 +90,18 @@ uint ObjectSpec::Index() const
 	return this - _object_specs;
 }
 
+/**
+ * Tie all ObjectSpecs to their class.
+ */
+/* static */ void ObjectSpec::BindToClasses()
+{
+	for (auto &spec : _object_specs) {
+		if (spec.IsEnabled() && spec.cls_id != INVALID_OBJECT_CLASS) {
+			ObjectClass::Assign(&spec);
+		}
+	}
+}
+
 /** This function initialize the spec arrays of objects. */
 void ResetObjects()
 {
@@ -104,20 +116,17 @@ void ResetObjects()
 	for (uint16 i = 0; i < lengthof(_original_objects); i++) {
 		_object_specs[i].grf_prop.local_id = i;
 	}
+
+	/* Set class for originals. */
+	_object_specs[OBJECT_LIGHTHOUSE].cls_id = ObjectClass::Allocate('LTHS');
+	_object_specs[OBJECT_TRANSMITTER].cls_id = ObjectClass::Allocate('TRNS');
 }
 
 template <typename Tspec, typename Tid, Tid Tmax>
 /* static */ void NewGRFClass<Tspec, Tid, Tmax>::InsertDefaults()
 {
-	ObjectClassID cls = ObjectClass::Allocate('LTHS');
-	ObjectClass::Get(cls)->name = STR_OBJECT_CLASS_LTHS;
-	_object_specs[OBJECT_LIGHTHOUSE].cls_id = cls;
-	ObjectClass::Assign(&_object_specs[OBJECT_LIGHTHOUSE]);
-
-	cls = ObjectClass::Allocate('TRNS');
-	ObjectClass::Get(cls)->name = STR_OBJECT_CLASS_TRNS;
-	_object_specs[OBJECT_TRANSMITTER].cls_id = cls;
-	ObjectClass::Assign(&_object_specs[OBJECT_TRANSMITTER]);
+	ObjectClass::Get(ObjectClass::Allocate('LTHS'))->name = STR_OBJECT_CLASS_LTHS;
+	ObjectClass::Get(ObjectClass::Allocate('TRNS'))->name = STR_OBJECT_CLASS_TRNS;
 }
 
 template <typename Tspec, typename Tid, Tid Tmax>
diff --git a/src/newgrf_object.h b/src/newgrf_object.h
index a441d3ceec..f283e36407 100644
--- a/src/newgrf_object.h
+++ b/src/newgrf_object.h
@@ -101,6 +101,8 @@ struct ObjectSpec {
 
 	static const ObjectSpec *Get(ObjectType index);
 	static const ObjectSpec *GetByTile(TileIndex tile);
+
+	static void BindToClasses();
 };
 
 /** Object scope resolver. */