Factual error: During the scene where Bruce leaves his girlfriend's parents home, it's raining. He leaves in a huff on his motorcycle and you can clearly hear the sound of screeching rubber on the pavement. Peeling out and making this sound would not have been possible in a rainstorm.
Continuity mistake: In the scene where Bruce is fighting in the restaurant with the other chinese guys, his shirt is stained with dirt in the back. The amount of dirt on his shirt changes from shot to shot.
Continuity mistake: Bruce lee fights with Johnny Sun for the first time. At a certain time, Bruce is laying on the ground and kicks Johnny on his shin/ankle. He kicks on the front so Johnny should fall towards the ground with his front. However, you can see Johnny falling flat on his back.