diff --git a/src/lerobot/policies/xvla/action_hub.py b/src/lerobot/policies/xvla/action_hub.py
index 0de151ec7..0caf35708 100644
--- a/src/lerobot/policies/xvla/action_hub.py
+++ b/src/lerobot/policies/xvla/action_hub.py
@@ -425,32 +425,25 @@ class BimanualSO101ActionSpace(BaseActionSpace):
         # Ensure both are [B, T, 20]
         pred = self._pad_to_model_dim(pred)
         target = self._pad_to_model_dim(target)
-        assert pred.shape == target.shape, "pred/target shapes must match"
-        batch_size, seq_len, action_dim = pred.shape
-        _ensure_indices_valid(action_dim, self.gripper_idx, "gripper_idx")
+        assert pred.shape == target.shape
 
-        # --- Gripper BCE loss (only real gripper indices) ---
-        g_losses = [self.bce(pred[:, :, gi], target[:, :, gi]) for gi in self.gripper_idx]
-        gripper_loss = sum(g_losses) / len(self.gripper_idx) * self.GRIPPER_SCALE
-
-        # --- Joint positions MSE (all non-gripper *real* dims) ---
-        real_set = set(self.REAL_IDXS)
-        joints_idx = tuple(i for i in real_set if i not in set(self.gripper_idx))
+        # ---- MSE for all real dims (0–11) ----
+        REAL_DIMS = 12
 
         joints_loss = self.mse(
-            pred[:, :, joints_idx],
-            target[:, :, joints_idx],
+            pred[:, :, :REAL_DIMS],
+            target[:, :, :REAL_DIMS],
         ) * self.JOINTS_SCALE
 
-        # Separate losses for left and right arms for better monitoring
-        left_arm_loss = self.mse(
-            pred[:, :, self.LEFT_ARM_JOINTS],
-            target[:, :, self.LEFT_ARM_JOINTS],
-        )
-        right_arm_loss = self.mse(
-            pred[:, :, self.RIGHT_ARM_JOINTS],
-            target[:, :, self.RIGHT_ARM_JOINTS],
-        )
+        left_arm_loss = self.mse(pred[:, :, :6],  target[:, :, :6])
+        right_arm_loss = self.mse(pred[:, :, 6:12], target[:, :, 6:12])
+
+        # is gripper continuous? not bce?
+        gripper_loss = self.mse(
+            pred[:, :, [5, 11]],
+            target[:, :, [5, 11]],
+        ) * self.GRIPPER_SCALE
+        
         return {
             "joints_loss": joints_loss,
             "gripper_loss": gripper_loss,