Stephen Kinzey used his experience riding his Harley-Davidson to teach about motion and physiology

 He researched the effects of video games on the health of children. And he chatted with his students about being a father and a devoted Catholic. That was Stephen Kinzey, tenured kinesiology professor at California State University, San Bernardino. But police said they know of another Stephen Kinzey, one who calls himself Skinz. This is the person who wore leathers and ran the local Devils Diciples motorcycle gang. He stashed guns and bricks of meth inside his tidy suburban home, police say. He fired off text messages to dealers: "Bring whatever cabbage u got for my soup cuz ingredients are low." Skinz, however, remains a mystery to Kinzey's friends and students. Even to his family. "This has to have an explanation. He's a Ph.D.," his father, Hank Kinzey, said shortly after his son was implicated. "Something knocked him off course." In September, Kinzey, 45, was charged with drug dealing, running a street gang and possessing illegal firearms. His girlfriend, former Cal State San Bernardino student Holly Robinson, is accused of helping him run a handful of meth dealers in what law-enforcement officials saw as a budding, small-time drug operation. Until his arrest, Kinzey's worst run-in with police was for a traffic ticket. But Kinzey appears to have cultivated a double life for years. While chairing the Kinesiology Department's curriculum committee, Kinzey was selling Devils Diciples T-shirts on E-Bay. He created two distinct Twitter personas. One is for Dr. Stephen J. Kinzey, featuring a profile picture of the human torso, used to chat with exercise physiology students. The other is for "skinz DDMC So Cal," a private account with a picture of him tearing down the road on his Harley. Investigators aren't sure what might have tempted Kinzey, if he indeed crossed over from being a weekend rider to being a hard-core biker. "He wasn't doing it for the profit. What was he doing it for? To be cool? I don't know. He has a job. He's a tenured professor," said San Bernardino County Deputy District Attorney Steven Sanchez, who heads the gang unit. "That's how a lot of guys move up. I can bring money into the club. I can increase our reputation." Mississippi roots Kinzey's romance with biker gangs started while he was teaching at the University of Mississippi in 1997, when he joined the local chapter of the Boozefighters Motorcycle Club just as he was getting a divorce, court records show. Its consummation occurred a little more than a decade ago, when he moved to San Bernardino County, birthplace of the Hells Angels and Vagos motorcycle gangs. Kinzey started two local motorcycle clubs in Southern California, but moved on or was forced out of both, before forming the mountain chapter of the Devils Diciples. It was a band of about six members from the San Bernardino Mountains and neighboring towns. There were recent signs of trouble. One Diciples member stabbed another biker last November outside of a popular biker hangout. Three others have been charged with possession of methamphetamine with intent to sell. Along with Kinzey, local Diciples members declined to comment for this article. But two people who know Kinzey said others in the chapter did not sanction a drug ring. The Devils Diciples started in Fontana, Calif., in 1967 but is now headquartered in Detroit, Kinzey's hometown. The club is believed to have about 150 members nationwide, and its website explicitly states it is a motorcycle enthusiasts' organization and "NOT a criminal organization." "Diciples" was purposely misspelled to distance the club from any religious affiliation. The Justice Department charged the club's former national president, Jeff Garvin "Fat Dog" Smith, with federal drug-trafficking charges in 2009, but months later it quietly dropped charges against him and 17 other Diciples members. In Southern California, the North Hollywood chapter is the largest, with smaller branches in Fontana, Montclair and the San Bernardino Mountains. "They're not as prominent as other biker gangs, but don't let that fool you. They're just as active," said Sheriff's Detective Jason Rosenbaum, who led the investigation against Kinzey. House raided When police raided Kinzey's house in August, they found a pound of meth, loaded handguns and rifles and "cuts" — biker leathers. The evidence needed for a search warrant was obtained when authorities tapped Kinzey's cellphone. They said they captured his text-message chatter with dealers and his supplier, leading them to Kinzey's suspected web of street dealers. But James Glick, Kinzey's defense attorney, said authorities had blown the case out of proportion. "This is not a major drug case," he said. "It's just because of what (Kinzey) does for a living." Glick also brushed aside allegations that the Devils Diciples is a criminal street gang. No other club members have been charged in the case, he said. "It's a motorcycle club," he said. "It's not like the Hells Angels." The day his house was raided, Kinzey was in Nebraska, on his way home after visiting his teenage daughter in Michigan, according to friends and family. Kinzey, who is on paid administrative leave from the university, turned himself in the next week and is out on bail. At Cal State San Bernardino, Kinzey has been a favorite among his students. He taught kinesiology, was a whiz with statistics and always made himself available to those who needed his help. "I could call him at 3 a.m. with a question, and he'd get back to me," said Nik Young, 25, a senior. "That's why I'm so shocked. It just doesn't seem like that'd be a part of a guy who is as positive and caring as he is." But Mike Lucas, senior kinesiology major who had Kinzey as his faculty adviser, said the professor's behavior started to change this past year. "He was always late for class," Lucas said. "He was distracted. You could tell there was something on his mind. It just seemed like he really didn't care that much anymore."