diff --git a/modules/menu/menu.admin.inc b/modules/menu/menu.admin.inc
index 66bd6f3..7da5ee7 100644
--- a/modules/menu/menu.admin.inc
+++ b/modules/menu/menu.admin.inc
@@ -59,6 +59,8 @@ function menu_overview_form($form, &$form_state, $menu) {
   foreach ($result as $item) {
     $links[] = $item;
   }
+  $weight_info = db_query("SELECT MAX(weight) AS max_weight, MIN(weight) as min_weight FROM {menu_links} WHERE menu_name = :menu", array(':menu' => $menu['menu_name']))->fetchObject();
+  $delta = max(abs($weight_info->min_weight), abs($weight_info->max_weight)) + 1;
   $tree = menu_tree_data($links);
   $node_links = array();
   menu_tree_collect_node_links($tree, $node_links);
@@ -67,7 +69,7 @@ function menu_overview_form($form, &$form_state, $menu) {
   menu_tree_check_access($tree, $node_links);
   $menu_admin = FALSE;
 
-  $form = array_merge($form, _menu_overview_tree_form($tree));
+  $form = array_merge($form, _menu_overview_tree_form($tree, $delta));
   $form['#menu'] =  $menu;
 
   if (element_children($form)) {
@@ -88,8 +90,10 @@ function menu_overview_form($form, &$form_state, $menu) {
  *
  * @param $tree
  *   The menu_tree retrieved by menu_tree_data.
+ * @param $delta
+ *   The number of items to use in the menu weight selector. Defaults to 50.
  */
-function _menu_overview_tree_form($tree) {
+function _menu_overview_tree_form($tree, $delta = 50) {
   $form = &drupal_static(__FUNCTION__, array('#tree' => TRUE));
   foreach ($tree as $data) {
     $title = '';
@@ -115,7 +119,7 @@ function _menu_overview_tree_form($tree) {
       );
       $form[$mlid]['weight'] = array(
         '#type' => 'weight',
-        '#delta' => 50,
+        '#delta' => $delta,
         '#default_value' => $item['weight'],
         '#title_display' => 'invisible',
         '#title' => t('Weight for @title', array('@title' => $item['title'])),
@@ -143,7 +147,7 @@ function _menu_overview_tree_form($tree) {
     }
 
     if ($data['below']) {
-      _menu_overview_tree_form($data['below']);
+      _menu_overview_tree_form($data['below'], $delta);
     }
   }
   return $form;
@@ -357,10 +361,26 @@ function menu_edit_item($form, &$form_state, $type, $item, $menu) {
     '#description' => t('The maximum depth for a link and all its children is fixed at !maxdepth. Some menu links may not be available as parents if selecting them would exceed this limit.', array('!maxdepth' => MENU_MAX_DEPTH)),
     '#attributes' => array('class' => array('menu-title-select')),
   );
+  // Get number of items in all possible parent menus so the weight selector is sized appropriately.
+  $menu_names = array_keys(menu_get_menus());
+  $menu_options = array();
+  foreach ($menu_names as $menu_name) {
+    if (isset($options[$menu_name . ':0'])) {
+      $menu_options[] = $menu_name;
+    }
+  }
+  // Make sure that we always have values in menu_options.
+  $menu_options = !empty($menu_options) ? $menu_options : $menu_names;
+  $weight_info = db_query("SELECT MAX(weight) AS max_weight, MIN(weight) as min_weight FROM {menu_links} WHERE menu_name IN (:menu_names)", array(':menu_names' => $menu_options))->fetchObject();
+  $delta = max(abs($weight_info->min_weight), abs($weight_info->max_weight)) + 1;
+  if ($delta < 50) {
+    // Old hardcoded value.
+    $delta = 50;
+  }
   $form['weight'] = array(
     '#type' => 'weight',
     '#title' => t('Weight'),
-    '#delta' => 50,
+    '#delta' => $delta,
     '#default_value' => $item['weight'],
     '#description' => t('Optional. In the menu, the heavier links will sink and the lighter links will be positioned nearer the top.'),
   );
diff --git a/modules/menu/menu.module b/modules/menu/menu.module
index 6444791..56a090f 100644
--- a/modules/menu/menu.module
+++ b/modules/menu/menu.module
@@ -701,6 +701,22 @@ function menu_form_node_form_alter(&$form, $form_state) {
     '#options' => $options,
     '#attributes' => array('class' => array('menu-parent-select')),
   );
+  // Get number of items in all possible parent menus so the weight selector is sized appropriately.
+  $menu_names = array_keys(menu_get_menus());
+  $menu_options = array();
+  foreach ($menu_names as $menu_name) {
+    if (isset($options[$menu_name . ':0'])) {
+      $menu_options[] = $menu_name;
+    }
+  }
+  // Make sure that we always have values in menu_options.
+  $menu_options = !empty($menu_options) ? $menu_options : $menu_names;
+  $weight_info = db_query("SELECT MAX(weight) AS max_weight, MIN(weight) as min_weight FROM {menu_links} WHERE menu_name IN (:menu_names)", array(':menu_names' => $menu_options))->fetchObject();
+  $delta = max(abs($weight_info->min_weight), abs($weight_info->max_weight)) + 1;
+  if ($delta < 50) {
+    // Old hardcoded value.
+    $delta = 50;
+  }
   $form['menu']['link']['weight'] = array(
     '#type' => 'weight',
     '#title' => t('Weight'),
diff --git a/modules/menu/menu.test b/modules/menu/menu.test
index 95e0ee9..70cbeab 100644
--- a/modules/menu/menu.test
+++ b/modules/menu/menu.test
@@ -211,6 +211,14 @@ class MenuTestCase extends DrupalWebTestCase {
     $this->assertMenuLink($item2['mlid'], array('depth' => 2, 'has_children' => 1, 'p1' => $item1['mlid'], 'p2' => $item2['mlid'], 'p3' => 0));
     $this->assertMenuLink($item3['mlid'], array('depth' => 3, 'has_children' => 0, 'p1' => $item1['mlid'], 'p2' => $item2['mlid'], 'p3' => $item3['mlid'], 'p4' => 0));
 
+    // Add 102 menu links with increasing weights, then make sure the last-added
+    // item's weight doesn't get changed because of the old hardcoded delta=50
+    $items = array();
+    for ($i = -50; $i <= 51; $i++) {
+      $items[$i] = $this->addMenuLink(0, 'node/' . $node1->nid, $menu_name, TRUE, strval($i));
+    }
+    $this->assertMenuLink($items[51]['mlid'], array('weight' => '51'));
+
     // Verify menu links.
     $this->verifyMenuLink($item1, $node1);
     $this->verifyMenuLink($item2, $node2, $item1, $node1);
@@ -281,9 +289,10 @@ class MenuTestCase extends DrupalWebTestCase {
    * @param integer $plid Parent menu link id.
    * @param string $link Link path.
    * @param string $menu_name Menu name.
+   * @param string $weight Menu link weight
    * @return array Menu link created.
    */
-  function addMenuLink($plid = 0, $link = '<front>', $menu_name = 'navigation', $expanded = TRUE) {
+  function addMenuLink($plid = 0, $link = '<front>', $menu_name = 'navigation', $expanded = TRUE, $weight = '0') {
     // View add menu link page.
     $this->drupalGet("admin/structure/menu/manage/$menu_name/add");
     $this->assertResponse(200);
@@ -296,7 +305,7 @@ class MenuTestCase extends DrupalWebTestCase {
       'enabled' => TRUE, // Use this to disable the menu and test.
       'expanded' => $expanded, // Setting this to true should test whether it works when we do the std_user tests.
       'parent' =>  $menu_name . ':' . $plid,
-      'weight' => '0',
+      'weight' => $weight,
     );
 
     // Add menu link.