diff --git a/lib/chef/knife/cookbook_github_install.rb b/lib/chef/knife/cookbook_github_install.rb
index ca3ecbd..dab16fb 100644
--- a/lib/chef/knife/cookbook_github_install.rb
+++ b/lib/chef/knife/cookbook_github_install.rb
@@ -141,7 +141,20 @@ def github_uri
       end
 
       def sha
-        @sha ||= noauth_rest.get_rest("http://github.com/api/v2/json/repos/show/#{@github_user}/#{@github_repo}/branches")['branches'][github_branch]
+        @sha ||= begin
+          data = nil
+          raise "Unable to find SHA checksum" unless ['heads','tags'].any? do |ref_type|
+            begin
+              data = noauth_rest.get_rest("https://api.github.com/repos/#{@github_user}/#{@github_repo}/git/refs/#{ref_type}/#{github_branch}")
+              ui.info("Found #{github_branch} amoung #{ref_type}.")
+              true
+            rescue
+              ui.info("Unable to find #{github_branch} among #{ref_type}.")
+              false
+            end
+          end
+          data['object']['sha']
+        end
       end
 
       def github_branch