diff --git a/boards/models/post.py b/boards/models/post.py
--- a/boards/models/post.py
+++ b/boards/models/post.py
@@ -441,7 +441,10 @@ class Post(models.Model, Viewable):
 
                 referenced_threads = referenced_post.get_threads().all()
                 for thread in referenced_threads:
+                    if thread.can_bump():
+                        thread.update_bump_status()
+
                     thread.last_edit_time = self.pub_time
-                    thread.save(update_fields=['last_edit_time'])
+                    thread.save(update_fields=['last_edit_time', 'bumpable'])
 
                     self.threads.add(thread)
diff --git a/boards/models/thread.py b/boards/models/thread.py
--- a/boards/models/thread.py
+++ b/boards/models/thread.py
@@ -73,12 +73,15 @@ class Thread(models.Model):
         if self.can_bump():
             self.bump_time = self.last_edit_time
 
-            if self.get_reply_count() >= settings.MAX_POSTS_PER_THREAD:
-                self.bumpable = False
-                self.update_posts_time()
+            self.update_bump_status()
 
             logger.info('Bumped thread %d' % self.id)
 
+    def update_bump_status(self):
+        if self.get_reply_count() >= settings.MAX_POSTS_PER_THREAD:
+            self.bumpable = False
+            self.update_posts_time()
+
     def get_reply_count(self):
         return self.get_replies().count()
 
@@ -189,3 +192,5 @@ class Thread(models.Model):
 
     def update_posts_time(self):
         self.post_set.update(last_edit_time=self.last_edit_time)
+        for post in self.post_set.all():
+            post.threads.update(last_edit_time=self.last_edit_time)