diff --git a/tests/test_basic.py b/tests/test_basic.py
index ac54b29..1cc7eaf 100644
--- a/tests/test_basic.py
+++ b/tests/test_basic.py
@@ -16,23 +16,28 @@ def test_auto_martini_imported():
     assert "auto_martini" in sys.modules
 
 
-@pytest.mark.parametrize("sdf_file", dpath.glob("*.sdf"))
-def test_auto_martini_run_sdf(sdf_file):
+@pytest.mark.parametrize(
+    "sdf_file,num_beads", 
+    [
+        (dpath / "benzene.sdf", 3),
+        (dpath / "ibuprofen.sdf", 5)
+    ]
+)
+def test_auto_martini_run_sdf(sdf_file: str, num_beads: int):
     mol = auto_martini.topology.gen_molecule_sdf(str(sdf_file))
-    auto_martini.solver.cg_molecule(mol, "MOL", "mol.top")
-    Path("mol.top").unlink()
+    cg_mol = auto_martini.solver.Cg_molecule(mol, "MOL")
+    assert len(cg_mol.cg_bead_names) == num_beads
 
 
 @pytest.mark.parametrize(
-    "smiles,top_file,name",
+    "smiles,top_file,name,num_beads",
     [
-        ("N1=C(N)NNC1N", "valid_GUA.top", "GUA"),
-        ("CCC", "valid_PRO.top", "PRO"),
+        ("N1=C(N)NNC1N", "valid_GUA.top", "GUA", 2),
+        ("CCC", "valid_PRO.top", "PRO", 1),
     ]
 )
-def test_auto_martini_run_smiles(smiles: str, top_file: Path, name: str):
+def test_auto_martini_run_smiles(smiles: str, top_file: Path, name: str, num_beads: int):
     mol, _ = auto_martini.topology.gen_molecule_smi(smiles)
-    auto_martini.solver.cg_molecule(mol, name, "mol.top")
+    cg_mol = auto_martini.solver.Cg_molecule(mol, name)
     # assert filecmp.cmp(dpath / top_file, "mol.top")
-    # need to figure out a better way of comparing contents
-    Path("mol.top").unlink()
+    assert len(cg_mol.cg_bead_names) == num_beads