diff --git a/kimm/models/ghostnet.py b/kimm/models/ghostnet.py
index e4c4bd8..92c1534 100644
--- a/kimm/models/ghostnet.py
+++ b/kimm/models/ghostnet.py
@@ -1,4 +1,5 @@
 import typing
+import warnings
 
 import keras
 from keras import backend
@@ -398,7 +399,7 @@ def __init__(
         dropout_rate: float = 0.2,
         classes: int = 1000,
         classifier_activation: str = "softmax",
-        weights: typing.Optional[str] = None,
+        weights: typing.Optional[str] = "imagenet",
         name: typing.Optional[str] = None,
         **kwargs,
     ):
@@ -409,6 +410,10 @@ def __init__(
             )
         kwargs = self.fix_config(kwargs)
         if len(getattr(self, "available_weights", [])) == 0:
+            warnings.warn(
+                f"{self.__class__.__name__} doesn't have pretrained weights "
+                f"for '{weights}'."
+            )
             weights = None
         super().__init__(
             width=self.width,
diff --git a/kimm/models/mobilenet_v3.py b/kimm/models/mobilenet_v3.py
index d604b14..1013b24 100644
--- a/kimm/models/mobilenet_v3.py
+++ b/kimm/models/mobilenet_v3.py
@@ -1,5 +1,6 @@
 import math
 import typing
+import warnings
 
 import keras
 from keras import layers
@@ -335,6 +336,10 @@ def __init__(
         if hasattr(self, "padding"):
             kwargs["padding"] = self.padding
         if len(getattr(self, "available_weights", [])) == 0:
+            warnings.warn(
+                f"{self.__class__.__name__} doesn't have pretrained weights "
+                f"for '{weights}'."
+            )
             weights = None
         super().__init__(
             width=self.width,
diff --git a/kimm/models/vision_transformer.py b/kimm/models/vision_transformer.py
index 52e73b6..0295676 100644
--- a/kimm/models/vision_transformer.py
+++ b/kimm/models/vision_transformer.py
@@ -1,4 +1,5 @@
 import typing
+import warnings
 
 import keras
 from keras import backend
@@ -176,6 +177,10 @@ def __init__(
             )
         kwargs = self.fix_config(kwargs)
         if len(getattr(self, "available_weights", [])) == 0:
+            warnings.warn(
+                f"{self.__class__.__name__} doesn't have pretrained weights "
+                f"for '{weights}'."
+            )
             weights = None
         super().__init__(
             patch_size=self.patch_size,