Since the holes on the KR808D-1 Models are on the
batteries instead of being on the cartomizers, some parts will not fit as "correctly" as they should when the cartomizers are twisted on all the way.
Try unscrewing the cartomizer to align the rectangular cutouts of the cartomizer with the holes in the battery.
When the holes in the battery are aligned with the rectangular cutouts on the cartomizer, you should be able to get a smoother draw out of it.
-Any