diff --git a/calibrate.py b/calibrate.py
index 054df78..c98ec15 100644
--- a/calibrate.py
+++ b/calibrate.py
@@ -2,12 +2,13 @@ from time import sleep
 import robot
 
 START_VALUES = [50, 50]
-THRESHOLD = 1.01
+THRESHOLD = 1.005
+SLEEP_TIME = 2
 
 def test_forward(arlo, l_power, r_power):
     arlo.reset_encoder_counts()
     arlo.go_diff(l_power, r_power, 1, 1)
-    sleep(1)
+    sleep(SLEEP_TIME)
     arlo.stop()
     return (
         int(arlo.read_left_wheel_encoder()),
@@ -17,7 +18,7 @@ def test_forward(arlo, l_power, r_power):
 def test_back(arlo, l_power, r_power):
     arlo.reset_encoder_counts()
     arlo.go_diff(l_power, r_power, 0, 0)
-    sleep(1)
+    sleep(SLEEP_TIME)
     arlo.stop()
     return (
         int(arlo.read_left_wheel_encoder()),
@@ -28,7 +29,7 @@ def test_back(arlo, l_power, r_power):
 def test_clockwise(arlo, l_power, r_power):
     arlo.reset_encoder_counts()
     arlo.go_diff(l_power, r_power, 1, 0)
-    sleep(1)
+    sleep(SLEEP_TIME)
     arlo.stop()
     return (
         int(arlo.read_left_wheel_encoder()),
@@ -38,7 +39,7 @@ def test_clockwise(arlo, l_power, r_power):
 def test_anticlockwise(arlo, l_power, r_power):
     arlo.reset_encoder_counts()
     arlo.go_diff(l_power, r_power, 0, 1)
-    sleep(1)
+    sleep(SLEEP_TIME)
     arlo.stop()
     return (
         int(arlo.read_left_wheel_encoder()),
@@ -46,7 +47,7 @@ def test_anticlockwise(arlo, l_power, r_power):
     )
 
 def main():
-    values = [START_VALUES for _ in range(4)]
+    values = [START_VALUES.copy() for _ in range(4)]
     calibrated = [False for _ in range(4)]
     tests = [
         test_forward,