He taught thousands of senseis how to run a dojo, all the while trading kicks onscreen with Lee and Chuck Norris.Bob Wall, a martial arts master who with quick business wits and even fleeter fists propelled disciplines like karate, aikido and Brazilian jiu-jitsu into the American mainstream, along the way making friends and sharing the screen with the likes of Bruce Lee and Chuck Norris, died on Jan. 30 in Los Angeles. He was 82.His wife, Lillian Wall, confirmed the death but did not provide a cause.For the millions of fans devoted to 1970s martial arts movies, Mr. Wall was best known for his role in the 1973 film “Enter the Dragon,” in which, as the thug O’Hara, he torments a vengeful undercover agent named Lee, played by Mr. Lee.At 6 feet 1 inch tall, with a full tuft of hair and a scraggly beard, Mr. Wall towered over the wiry, diminutive Mr. Lee, who, in the film, nevertheless overpowers his adversary by kicking him to the ground and crushing his chest. It’s an indelibly grisly moment, and a sharp contrast to the close bond the two men shared in real life.They had met in 1963, at a kung fu demonstration in Los Angeles’s Chinatown neighborhood, where Mr. Wall had withstood the instructor’s blows without dropping his beer.“At that point reality hit that I’d blown this guy’s demo, so I started walking toward the door,” Mr. Wall recalled in a 2011 interview. “I saw this tough-looking guy walking toward me, so I said, ‘This guy, I’m gonna clock,’ and he walks up close to me and says, ‘Hey that was funny. I’m Bruce Lee!’”They ended up talking in the parking lot for three hours.Mr. Lee was still an unknown martial arts instructor in Oakland who, like Mr. Wall, was drawn to Los Angeles’s budding combat-sports scene. Mr. Wall was a student of another instructor, Mr. Norris, an Air Force veteran and martial arts champion.The three became fast friends, and in 1967 Mr. Wall and Mr. Norris went into business together, running a series of studios in the San Fernando Valley, a part of Los Angeles that two decades later would provide the setting for “The Karate Kid.”Martial arts was an exclusively male domain at the time, fought without padding and producing more than a few broken noses and cracked teeth. But entrepreneurs like Mr. Wall saw an opportunity to make studios more professional and family friendly. Through manuals and seminars that he took around the country, he taught thousands of aspiring senseis how to run a dojo.“There were a lot of people who would open a school and start teaching and it would all fall into place or not,” Roy Kurban, a taekwondo champion who was inspired by Mr. Wall to open his own studio in Fort Worth, Texas, said in a phone interview. “He built a business system.”Mr. Lee, meanwhile, had begun his steady rise to global stardom. An appearance at the 1964 International Karate Championships in Long Beach, where he demonstrated his signature moves like the two-finger push up and the one-inch punch, led him to a role as Kato, the sidekick on the 1960s TV show “The Green Hornet,” and later to a series of movie deals.From left, Chuck Norris, Mr. Lee and Mr. Wall. The three became fast friends and Mr. Wall and Mr. Norris ran a series of martial arts studios together.via Wall familyMartial arts movies were huge in Asia but largely unknown in the United States. Mr. Lee decided to change that, in part by incorporating roles for Black and white actors, including Mr. Wall, who won a part alongside Mr. Norris in Mr. Lee’s first major film released in America, “The Way of the Dragon” (1972).Mr. Wall could take a hit, which put him in good stead with Mr. Lee, who insisted on doing his own stunts and refused to pull punches during fight scenes. Mr. Wall recalled that before they started filming “Enter the Dragon,” Mr. Lee told him, “Bob, I wanna hit you, and I wanna hit you hard.”Even the broken bottles that O’Hara wields against Lee were real — which presented a problem when Mr. Lee, a perfectionist, insisted on shooting that part of the scene nine times, with Mr. Wall repeatedly falling back on shards of glass. At another point Mr. Lee kicked him so hard that he flew back into a row of extras, breaking a man’s arm.“It’s one thing to get hit that hard once or twice, but try it eight times in a row,” Mr. Wall said. “Let me tell you, about the fourth time, you know what’s coming, you’re going to get popped real hard, and you just have to say, ‘Hey, I’m here to do a job. Make it real.’”That commitment to combat vérité paid off. “Enter the Dragon,” made for just $850,000 (about $5.3 million in today’s dollars) grossed $350 million worldwide (about $2.2 billion today), making it one of the most profitable movies of all time. It helped establish martial arts as an indelible part of American pop culture.But Mr. Lee did not get to enjoy the success. He died, at 32, just before the film debuted, of undiagnosed swelling in his brain. By then he had begun filming “Game of Death,” featuring an iconic fight scene with Kareem Abdul-Jabbar (the film, in which Mr. Wall also had a role, was released in 1978). And he was planning even more movies, including at least one with a prominent role for Mr. Wall, who would play a sidekick to Mr. Lee’s hero, a C.I.A. agent.“Hey Bob,” Mr. Wall recalled him saying a few weeks before his death, “you get to be a good guy in the next one!”Mr. Wall in 2008. Later in life, he found a second career in real estate as a residential and commercial developer.AlamyRobert Alan Wall was born on Aug. 22, 1939, in San Jose, Calif. His father, Ray Wall, worked in construction and his mother, Reva (Wingo) Wall, was a nurse.He was drawn to martial arts as a young teenager who had suffered beatings at the hands of his abusive, alcoholic father. He wrestled in high school and at San Jose State University, where he left without graduating to join the Army. After he was discharged, he moved to Los Angeles to begin his martial arts education under Mr. Norris.Mr. Wall held an advanced black belt in several disciplines, and he regularly placed first or second at competitions around the country in the late 1960s and early ’70s.After Mr. Lee’s death, he worked as a fight coordinator on several martial arts movies, including “Black Belt Jones” (1974), starring one of his protégés, Jim Kelly, one of the first Black karate champions. He also gave private lessons to celebrities interested in martial arts, including Steve McQueen and Elvis Presley.By the mid-1970s Mr. Norris had decided to go into acting full time, and he and Mr. Wall sold their business in 1975. Mr. Wall turned his attention to real estate, launching a second career as a residential and commercial developer. He didn’t leave the world of martial arts, though. In addition to writing books and teaching seminars, he had a long-running and very public beef with Steven Seagal, another martial arts expert turned action star.In a series of interviews in the mid-1980s, Mr. Seagal, who had taught aikido in Japan, insulted American martial arts, and Mr. Norris in particular. In response, Mr. Wall challenged him to a fight; they never came to blows, and eventually they worked it out, but Mr. Wall refused to watch any of Mr. Seagal’s movies.Mr. Wall also remained close friends with Mr. Norris. He took small roles in several of his movies and on the series “Walker, Texas Ranger,” which starred Mr. Norris and ran from 1993 to 2001.It was just the right amount of fame for Mr. Wall.“I’m famous enough that people who know martial arts or know Bruce Lee films know me,” he said. “But I’m not so famous that I can’t walk down a street. I can go in and out of a restaurant. I don’t lose my privacy.” More