diff --git a/src/karts/kart.cpp b/src/karts/kart.cpp
index 08f3ba3d1..237f63e5d 100644
--- a/src/karts/kart.cpp
+++ b/src/karts/kart.cpp
@@ -1541,7 +1541,8 @@ void Kart::updatePhysics(float dt)
     {
         m_has_started = true;
         float f       = m_kart_properties->getStartupBoost();
-        m_vehicle->activateZipper(f);
+        if(f>0)
+            m_vehicle->activateZipper(f);
         MaxSpeed::increaseMaxSpeed(MS_INCREASE_ZIPPER, 0.9f*f,
                                    5.0f, 5.0f);