diff --git a/test/test_node.rb b/test/test_node.rb
index 9d1acb0..0e83e4c 100755
--- a/test/test_node.rb
+++ b/test/test_node.rb
@@ -189,7 +189,7 @@ def test_sim_time
     end
     clock_pub.publish(time_msg)
 
-    sleep 0.5
+    sleep 1.0
 
     sim_current = ROS::Time.now
     assert_equal(time_msg.clock, sim_current)
diff --git a/test/test_rate.rb b/test/test_rate.rb
index edddfe5..f9a8676 100755
--- a/test/test_rate.rb
+++ b/test/test_rate.rb
@@ -5,6 +5,8 @@
 
 class TestRate_rate < Test::Unit::TestCase
   def test_sleep
+    param = ROS::ParameterManager.new(ENV['ROS_MASTER_URI'], '/use_sim_time', {})
+    param.set_param('/use_sim_time', false)
     r = ROS::Rate.new(10)
     (1..10).each do |i|
       start = ::Time.now