diff --git a/src/simplex/tests/test_simplex.real.ml b/src/simplex/tests/test_simplex.real.ml
index 9acd6540..df0b88ac 100644
--- a/src/simplex/tests/test_simplex.real.ml
+++ b/src/simplex/tests/test_simplex.real.ml
@@ -132,7 +132,7 @@ module Step = struct
                let v = List.length vars in
                let gen =
                  let* vars' = G.shuffle_l vars in
-                 let* n = 1 -- List.length vars' in
+                 let* n = 1 -- min 12 (List.length vars') in
                  let vars' = CCList.take n vars' in
                  assert (List.length vars' = n);
                  let* coeffs = list_repeat n rand_q.gen in