diff --git a/examples/chat_websocket/config.ru b/examples/chat_websocket/config.ru
index 6dd5948..e67ea69 100644
--- a/examples/chat_websocket/config.ru
+++ b/examples/chat_websocket/config.ru
@@ -16,6 +16,8 @@ end
 
 module ChatRamp
   class HomeAction < Cramp::Action
+    self.transport = :chunked
+
     template_path = File.join(File.dirname(__FILE__), 'views/index.erb')
     @@template = Erubis::Eruby.new(File.read(template_path))
 
diff --git a/lib/cramp/action.rb b/lib/cramp/action.rb
index 0c5dd7e..ca7e94e 100644
--- a/lib/cramp/action.rb
+++ b/lib/cramp/action.rb
@@ -38,6 +38,8 @@ def build_headers
         [status, headers.merge(self.default_sse_headers)]
       when :chunked
         status, headers = respond_to?(:respond_with, true) ? respond_with : [200, {}]
+        headers['Content-Type'] ||= 'text/html'
+
         [status, headers.merge(self.default_chunked_headers)]
       else
         super
diff --git a/test/controller/chunked_transport_test.rb b/test/controller/chunked_transport_test.rb
index 7790e81..50ba504 100644
--- a/test/controller/chunked_transport_test.rb
+++ b/test/controller/chunked_transport_test.rb
@@ -21,6 +21,7 @@ def test_headers
     get '/' do |status, headers, body|
       assert_equal 200, status
       assert_equal "chunked", headers["Transfer-Encoding"]
+      assert_equal "text/html", headers["Content-Type"]
       assert_kind_of Cramp::Body, body
 
       EM.stop