diff --git a/birdie.py b/birdie.py
index e14762f..c5f4871 100644
--- a/birdie.py
+++ b/birdie.py
@@ -37,8 +37,8 @@ def update():
     if titi2.y > 708 :
         titi2.y = 0
     vitesse_defilement = 1
-    tube_sup.x += vitesse_defilement
-    tube_inf.x += vitesse_defilement
+    tube_sup.x -= vitesse_defilement
+    tube_inf.x -= vitesse_defilement
     if tube_sup.x + tube_sup.width/2< 0 :
         tube_sup.x = WIDTH + tube_sup.width/2
         tube_inf.x = WIDTH + tube_sup.width/2