Tuned drive

Change-Id: I6e174df4a55195bde9605b49b8ed42cb4b62eb99
diff --git a/y2016_bot3/control_loops/python/drivetrain.py b/y2016_bot3/control_loops/python/drivetrain.py
index 5a67416..5de7dbc 100755
--- a/y2016_bot3/control_loops/python/drivetrain.py
+++ b/y2016_bot3/control_loops/python/drivetrain.py
@@ -71,9 +71,9 @@
     # Free Current in Amps
     self.free_current = 4.7 * self.num_motors
     # Moment of inertia of the drivetrain in kg m^2
-    self.J = 2.0
+    self.J = 8.0
     # Mass of the robot, in kg.
-    self.m = 68
+    self.m = 45
     # Radius of the robot, in meters (requires tuning by hand)
     self.rb = 0.601 / 2.0
     # Radius of the wheels, in meters.