diff --git a/interfaces/cython/cantera/onedim.py b/interfaces/cython/cantera/onedim.py
index 69917de7a..5b749795b 100644
--- a/interfaces/cython/cantera/onedim.py
+++ b/interfaces/cython/cantera/onedim.py
@@ -407,7 +407,7 @@ class FreeFlame(FlameBase):
 
         if not self.inlet.mdot:
             # nonzero initial guess increases likelihood of convergence
-            self.inlet.mdot = 1.0
+            self.inlet.mdot = 1.0 * self.gas.density
 
         # get adiabatic flame temperature and composition
         self.gas.equilibrate('HP')