diff --git a/examples/rmg/SR_test/input.py b/examples/rmg/SR_test/input.py
index 692c239e50f..d94eafa6257 100644
--- a/examples/rmg/SR_test/input.py
+++ b/examples/rmg/SR_test/input.py
@@ -21,19 +21,27 @@
     structure=SMILES('[O][O]')
 )
 
+species(
+   label='N2',
+   reactive=False,
+   structure=SMILES('N#N'),
+)
+
 # Reaction systems
 simpleReactor(
     temperature=[(1000,'K'),(1500,'K')],
     pressure=[(1.0,'bar'),(10.0,'bar')],
-    nSimsTerm=12, #24 is probably a better number for 2-D input conditions like these
+    nSimsTerm=12, 
     initialMoleFractions={
-        "ethane": 0.1,
-        "O2": 0.9
+        "ethane": [0.05,0.15],
+        "O2": 0.1,
+        "N2": 0.9,
     },
     terminationConversion={
         'ethane': 0.1,
     },
     terminationTime=(1e1,'s'),
+    balanceSpecies = "N2",
 )
 
 simulator(