diff --git a/gunicorn/config.py b/gunicorn/config.py
index de1f7b0f..ab6b276f 100644
--- a/gunicorn/config.py
+++ b/gunicorn/config.py
@@ -821,13 +821,14 @@ class PreloadApp(Setting):
         restarting workers.
         """
 
+
 class Sendfile(Setting):
     name = "sendfile"
     section = "Server Mechanics"
     cli = ["--no-sendfile"]
     validator = validate_bool
-    action = "store_false"
-    default = True
+    action = "store_const"
+    const = False
     desc = """\
         Disables the use of ``sendfile()``.
 
@@ -837,6 +838,7 @@ class Sendfile(Setting):
            disabling.
         """
 
+
 class Chdir(Setting):
     name = "chdir"
     section = "Server Mechanics"
diff --git a/gunicorn/http/wsgi.py b/gunicorn/http/wsgi.py
index f76d722d..c537166e 100644
--- a/gunicorn/http/wsgi.py
+++ b/gunicorn/http/wsgi.py
@@ -347,7 +347,7 @@ class Response(object):
         util.write(self.sock, arg, self.chunked)
 
     def can_sendfile(self):
-        return self.cfg.sendfile and sendfile is not None
+        return self.cfg.sendfile is not False and sendfile is not None
 
     def sendfile(self, respiter):
         if self.cfg.is_ssl or not self.can_sendfile():