diff --git a/mlair/data_handler/data_handler_kz_filter.py b/mlair/data_handler/data_handler_kz_filter.py
index 1ff1a36f61670383e1f3bf9314045e799be7394d..1f2c63e58c7eaab645f074ac953d2f05d8ba09fd 100644
--- a/mlair/data_handler/data_handler_kz_filter.py
+++ b/mlair/data_handler/data_handler_kz_filter.py
@@ -8,6 +8,7 @@ import numpy as np
 import pandas as pd
 import xarray as xr
 from typing import List, Union
+from functools import partial
 
 from mlair.data_handler.data_handler_single_station import DataHandlerSingleStation
 from mlair.data_handler import DefaultDataHandler
@@ -83,6 +84,14 @@ class DataHandlerKzFilterSingleStation(DataHandlerSingleStation):
         return self.history.transpose(self.time_dim, self.window_dim, self.iter_dim, self.target_dim,
                                       self.filter_dim).copy()
 
+    def _create_lazy_data(self):
+        return [self._data, self.meta, self.input_data, self.target_data, self.cutoff_period, self.cutoff_period_days]
+
+    def _extract_lazy(self, lazy_data):
+        _data, self.meta, _input_data, _target_data, self.cutoff_period, self.cutoff_period_days = lazy_data
+        f_prep = partial(self._slice_prep, start=self.start, end=self.end)
+        self._data, self.input_data, self.target_data = list(map(f_prep, [_data, _input_data, _target_data]))
+
 
 class DataHandlerKzFilter(DefaultDataHandler):
     """Data handler using kz filtered data."""
diff --git a/mlair/data_handler/data_handler_mixed_sampling.py b/mlair/data_handler/data_handler_mixed_sampling.py
index acb62df9ce1fd9b61889c0b97973c953e9bda1ff..b359a26df539e95736650a9d8fc5116ea68db8ee 100644
--- a/mlair/data_handler/data_handler_mixed_sampling.py
+++ b/mlair/data_handler/data_handler_mixed_sampling.py
@@ -12,9 +12,6 @@ import inspect
 from typing import Callable
 import datetime as dt
 from typing import Any
-import os
-import dill
-import logging
 from functools import partial
 
 import numpy as np
@@ -158,9 +155,6 @@ class DataHandlerMixedSamplingWithFilterSingleStation(DataHandlerMixedSamplingSi
                                 limit=self.interpolation_limit[ind])
         return data
 
-    def _create_lazy_data(self):
-        return [self._data, self.meta, self.input_data, self.target_data, self.cutoff_period, self.cutoff_period_days]
-
     def _extract_lazy(self, lazy_data):
         _data, self.meta, _input_data, _target_data, self.cutoff_period, self.cutoff_period_days = lazy_data
         start_inp, end_inp = self.update_start_end(0)
diff --git a/mlair/data_handler/data_handler_single_station.py b/mlair/data_handler/data_handler_single_station.py
index a8c6ea2e021251b72a9699426dc179d82fcb4e6d..0497bee0ae6b6a72301181ef5453dd40f479e5af 100644
--- a/mlair/data_handler/data_handler_single_station.py
+++ b/mlair/data_handler/data_handler_single_station.py
@@ -61,11 +61,11 @@ class DataHandlerSingleStation(AbstractDataHandler):
                  interpolation_method: Union[str, Tuple[str]] = DEFAULT_INTERPOLATION_METHOD,
                  overwrite_local_data: bool = False, transformation=None, store_data_locally: bool = True,
                  min_length: int = 0, start=None, end=None, variables=None, data_origin: Dict = None,
-                 lazy_loading: bool = False, **kwargs):
+                 lazy_preprocessing: bool = False, **kwargs):
         super().__init__()
         self.station = helpers.to_list(station)
         self.path = self.setup_data_path(data_path, sampling)
-        self.lazy = lazy_loading
+        self.lazy = lazy_preprocessing
         self.lazy_path = None
         if self.lazy is True:
             self.lazy_path = os.path.join(data_path, "lazy_data", self.__class__.__name__)
@@ -252,9 +252,7 @@ class DataHandlerSingleStation(AbstractDataHandler):
             with open(filename, "rb") as pickle_file:
                 lazy_data = dill.load(pickle_file)
             self._extract_lazy(lazy_data)
-            logging.info("<<<loaded lazy file")
         except FileNotFoundError:
-            logging.info(">>>could not load lazy file")
             self.make_input_target()
 
     def _extract_lazy(self, lazy_data):