got the new drive code working
diff --git a/frc971/control_loops/python/drivetrain.py b/frc971/control_loops/python/drivetrain.py
index 27bebbc..c6a3f05 100755
--- a/frc971/control_loops/python/drivetrain.py
+++ b/frc971/control_loops/python/drivetrain.py
@@ -62,7 +62,7 @@
     self.free_current = 2.7
     # Moment of inertia of the drivetrain in kg m^2
     # Just borrowed from last year.
-    self.J = 6.4
+    self.J = 4.5
     # Mass of the robot, in kg.
     self.m = 68
     # Radius of the robot, in meters (from last year).