Continuity mistake: When Daniel and Mr. Miyagi are in the Kobra Kai Dojo speaking with the Sensai, in one shot the Sensai points at Daniel, who is standing beside Mr. Miyagi. Then in the following shot, when the Sensai is pointing his finger at Mr. Miyagi, Daniel is now standing behind Mr. Miyagi. (00:49:45)
Continuity mistake: When Johnny is walking away from Ali, the shot cuts to Daniel lying down on the sand, and there are two guys behind him, one with brown hair and a red tie around his head and a blonde guy. In the following shot after the line "Where did you find this guy," the two guys are now shoulder to shoulder with the guy in the yellow shirt. (00:13:35)
Continuity mistake: When Daniel and his mother are in their new apartment, Daniel goes over to the sink to fill up a bowl of water. The two items on the top by the sink appear in the first shot, then disappear in a shot from behind Daniel then reappear again in a shot from the front. (00:06:45)
Continuity mistake: In the very beginning, when Daniel and his mom start to drive away from their old house in New Jersey, Daniel's bike is strapped to the roof of the station wagon. The bike is positioned with the front tire of the bike facing the back of the vehicle. A couple seconds later, in the very next cut scene, the bike is facing the opposite direction.
Continuity mistake: When Mr. Myagi and Daniel go to the dojo to stop the fighting, the earlier scene revealed that they left the apartment at 10am. Assuming that there was some time to get to the dojo, they left a few minutes later and then drove to Mr. Myagi's house to start the training. Daniel starts to wax the cars and the sky is showing a sunset. At the latest, it may have been around 11am when they got to the house, so there is no way the sun could be setting.