diff --git a/operator-framework-core/src/test/java/io/javaoperatorsdk/operator/processing/event/internal/TimerEventSourceTest.java b/operator-framework-core/src/test/java/io/javaoperatorsdk/operator/processing/event/internal/TimerEventSourceTest.java
index cf95374b2e..4ad431d05d 100644
--- a/operator-framework-core/src/test/java/io/javaoperatorsdk/operator/processing/event/internal/TimerEventSourceTest.java
+++ b/operator-framework-core/src/test/java/io/javaoperatorsdk/operator/processing/event/internal/TimerEventSourceTest.java
@@ -22,7 +22,7 @@ class TimerEventSourceTest {
 
   public static final int INITIAL_DELAY = 50;
   public static final int PERIOD = 50;
-  public static final int TESTING_TIME_SLACK = 20;
+  public static final int TESTING_TIME_SLACK = 40;
 
   private TimerEventSource timerEventSource;
   private EventHandler eventHandlerMock = mock(EventHandler.class);