Director Robert Clouse was deaf and was reliant on his assistant directors to hear the dialogue and verify that it had been delivered effectively as was done on his other pictures.
The color, make and model of the car that Black Belt Jones Jim Kelly drives is a yellow and black 1971 Jensen Interceptor Mk III. This is a hand-made British import powered by a 440 c.i. Chrysler engine.
According to 'Every '70s Movie', ''...the confusion over whether 'Hot Potato' is a real sequel to La Ceinture noire (1974) is compounded by the existence of a totally unrelated Jim Kelly movie called Black kung fu contre Hong Kong connection (1978), which is sometimes deceptively marketed as 'Black Belt Jones 2' [and/or 'Black Belt Jones 2: The Tattoo Connection']''. (In Tattoo Connection, Jim Kelly's name is Lucas, not Jones, and was referred to as Black Belt Jones 2 for financial purposes. In Hot Potato, Kelly's name is, again, Jones. Also, the same producer and writer turned director, Alexandra Rose and Oscar Williams, made Hot Potato after this movie, so it IS a genuine sequel, but more a 'further adventure' kind of thing, like the James Bond franchise.)
A studio press release from Warner Bros., Inc. announced that the movie's lead cast members Jim Kelly and Gloria Hendry would be travelling across the states to promote the picture on separate cross-country tours of the USA. Their destinations included Miami, New York, Chicago, Atlanta, Columbus, Baltimore, New Orleans and Philadelphia.
Second film in a three picture deal between star Jim Kelly and the Warner Bros. studio. The two other films were Opération Dragon (1973) and Faut pas karaté la queue du tigre (1976).