diff --git a/.github/sync-repo-settings.yaml b/.github/sync-repo-settings.yaml
index 0ddb512d..3e98ae70 100644
--- a/.github/sync-repo-settings.yaml
+++ b/.github/sync-repo-settings.yaml
@@ -1,9 +1,9 @@
-# https://github.com/googleapis/repo-automation-bots/tree/master/packages/sync-repo-settings
-# Rules for master branch protection
+# https://github.com/googleapis/repo-automation-bots/tree/main/packages/sync-repo-settings
+# Rules for main branch protection
 branchProtectionRules:
 # Identifies the protection rule pattern. Name of the branch to be protected.
-# Defaults to `master`
-- pattern: master
+# Defaults to `main`
+- pattern: main
   requiresCodeOwnerReviews: true
   requiresStrictStatusChecks: true
   requiredStatusCheckContexts:
diff --git a/owlbot.py b/owlbot.py
index 9857c5b2..6e278dd7 100644
--- a/owlbot.py
+++ b/owlbot.py
@@ -106,6 +106,65 @@
         '\n',
     )
 
+    # Remove the replacements below once
+    # https://github.com/googleapis/synthtool/pull/1188 is merged
+
+    # Update googleapis/repo-automation-bots repo to main in .kokoro/*.sh files
+    s.replace(
+        ".kokoro/*.sh",
+        "repo-automation-bots/tree/master",
+        "repo-automation-bots/tree/main",
+    )
+
+    # Customize CONTRIBUTING.rst to replace master with main
+    s.replace(
+        "CONTRIBUTING.rst",
+        "fetch and merge changes from upstream into master",
+        "fetch and merge changes from upstream into main",
+    )
+
+    s.replace(
+        "CONTRIBUTING.rst",
+        "git merge upstream/master",
+        "git merge upstream/main",
+    )
+
+    s.replace(
+        "CONTRIBUTING.rst",
+        """export GOOGLE_CLOUD_TESTING_BRANCH=\"master\"""",
+        """export GOOGLE_CLOUD_TESTING_BRANCH=\"main\"""",
+    )
+
+    s.replace(
+        "CONTRIBUTING.rst",
+        "remote \(``master``\)",
+        "remote (``main``)",
+    )
+
+    s.replace(
+        "CONTRIBUTING.rst",
+        "blob/master/CONTRIBUTING.rst",
+        "blob/main/CONTRIBUTING.rst",
+    )
+
+    s.replace(
+        "CONTRIBUTING.rst",
+        "blob/master/noxfile.py",
+        "blob/main/noxfile.py",
+    )
+
+    s.replace(
+        "docs/conf.py",
+        "master_doc",
+        "root_doc",
+    )
+
+    s.replace(
+        "docs/conf.py",
+        "# The master toctree document.",
+        "# The root toctree document.",
+    )
+
     s.move(
         library,
         excludes=[