diff --git a/rhodecode/model/repo.py b/rhodecode/model/repo.py
--- a/rhodecode/model/repo.py
+++ b/rhodecode/model/repo.py
@@ -36,11 +36,8 @@ log = logging.getLogger(__name__)
 
 class RepoModel(object):
 
-    def __init__(self, sa=None):
-        if not sa:
-            self.sa = Session()
-        else:
-            self.sa = sa
+    def __init__(self):
+        self.sa = Session()
 
     def get(self, repo_id, cache=False):
         repo = self.sa.query(Repository)\
@@ -67,7 +64,7 @@ class RepoModel(object):
             #update permissions
             for username, perm in form_data['perms_updates']:
                 r2p = self.sa.query(RepoToPerm)\
-                        .filter(RepoToPerm.user == UserModel(self.sa).get_by_username(username, cache=False))\
+                        .filter(RepoToPerm.user == UserModel().get_by_username(username, cache=False))\
                         .filter(RepoToPerm.repository == self.get(repo_name))\
                         .one()
 
@@ -80,7 +77,7 @@ class RepoModel(object):
             for username, perm in form_data['perms_new']:
                 r2p = RepoToPerm()
                 r2p.repository = self.get(repo_name)
-                r2p.user = UserModel(self.sa).get_by_username(username, cache=False)
+                r2p.user = UserModel().get_by_username(username, cache=False)
 
                 r2p.permission_id = self.sa.query(Permission).filter(
                                         Permission.permission_name == perm)\
@@ -134,7 +131,7 @@ class RepoModel(object):
             #create default permission
             repo_to_perm = RepoToPerm()
             default = 'repository.read'
-            for p in UserModel(self.sa).get_by_username('default', cache=False).user_perms:
+            for p in UserModel().get_by_username('default', cache=False).user_perms:
                 if p.permission.permission_name.startswith('repository.'):
                     default = p.permission.permission_name
                     break
@@ -146,7 +143,7 @@ class RepoModel(object):
                     .one().permission_id
 
             repo_to_perm.repository_id = new_repo.repo_id
-            repo_to_perm.user_id = UserModel(self.sa).get_by_username('default', cache=False).user_id
+            repo_to_perm.user_id = UserModel().get_by_username('default', cache=False).user_id
 
             self.sa.add(repo_to_perm)
             self.sa.commit()