diff --git a/neurodiffeq/solvers.py b/neurodiffeq/solvers.py
index 160552d..e950655 100644
--- a/neurodiffeq/solvers.py
+++ b/neurodiffeq/solvers.py
@@ -1357,7 +1357,7 @@ def __init__(self, ode_system, conditions, t_min, t_max,
 
         def _diff_eqs_wrapper(*variables):
             funcs_and_coords = variables[:N_FUNCTIONS + N_COORDS]
-            eq_params = tuple(variables[idx] for idx in eq_param_index)
+            eq_params = tuple(variables[idx] for idx in self.eq_param_index)
             return ode_system(*funcs_and_coords, *eq_params)
 
         super(BundleSolver1D, self).__init__(
diff --git a/neurodiffeq/solvers_utils.py b/neurodiffeq/solvers_utils.py
index 36e7ba9..ca97712 100644
--- a/neurodiffeq/solvers_utils.py
+++ b/neurodiffeq/solvers_utils.py
@@ -530,7 +530,9 @@ def load(cls,
                          t_min=t_min,
                          t_max=t_max,
                          theta_min=tuple(load_dict['solver'].r_min[1:]),
-                         theta_max=tuple(load_dict['solver'].r_max[1:]))
+                         theta_max=tuple(load_dict['solver'].r_max[1:]),
+                         eq_param_index=load_dict['solver'].eq_param_index
+            )
 
         if best_nets != None:
             solver.best_nets = best_nets