diff --git a/ultralytics/models/rtdetr/train.py b/ultralytics/models/rtdetr/train.py
index cb11a72794..962aeaf9bc 100644
--- a/ultralytics/models/rtdetr/train.py
+++ b/ultralytics/models/rtdetr/train.py
@@ -68,8 +68,11 @@ class RTDETRTrainer(DetectionTrainer):
             hyp=self.args,
             rect=False,
             cache=self.args.cache or None,
+            single_cls=self.args.single_cls or False,
             prefix=colorstr(f"{mode}: "),
+            classes=self.args.classes,
             data=self.data,
+            fraction=self.args.fraction if mode == "train" else 1.0,
         )
 
     def get_validator(self):