Knievel, who died last November in Clearwater, Fla., repeatedly denied his involvement to both investigators and victims, according to the documents.
"Knievel stated that he was not responsible for what just happened to (name redacted) and that he had no control over the 'thing'" according to one phone conversation recounted in an FBI interview.
Knievel, immortalized in the Smithsonian Institution as "America's Legendary Daredevil," donned red, white and blue for his death-defying stunts. He had a knack for outrageous yarns and claimed to have been a swindler, a card thief, a safe cracker and a holdup man.
His most well-known run-in with the law was a 1977 attack on movie studio executive Shelly Saltman, whom the daredevil beat with a baseball bat in the parking lot of 20th Century Fox.
Saltman promoted Knievel's infamous attempt to jump Idaho's Snake River Canyon and then wrote a book about the experience, angering Knievel by portraying him as "an alcoholic, a pill addict, an anti-Semite and an immoral person."
Knievel was sentenced to six months in jail and Saltman won a $12.75 million judgment, but never collected. Saltman did not return a phone message recently to discuss the FBI file.
Knievel's file shows investigators believed he was involved with other violent acts - a threat in Phoenix, an attack in a Kansas City hotel room and a vicious beating in San Francisco. All were allegedly carried out by Knievel associates, according to subjects quoted in the file.
The investigation bounced between field offices in Miami, Chicago and California. Knievel's business associates were interviewed, his phone records examined.
Of the 202 pages of Knievel's 290-page file released to the AP, some were heavily redacted, with identities, interviews and contact information excluded. The names of victims were not released, though some details of their experiences were.
One man told agents he received a threatening phone call, and shortly after was beaten by a Knievel associate who left him hospitalized. The man was interviewed by the FBI, but could remember his assailant's black loafers better than his facial features.
He told the AP he wants to remain anonymous because he had moved on from the attack and into a career not associated with stunt jumping. He said the FBI wanted to know if he could identify his attacker.
"They gave me mug shots at one point in time and I couldn't pick him out," he said. "It was a dark room, he had dark glasses on him. All I know is he was big. I could describe his shoes better than anything."
Authorities first wanted to charge Knievel with violations of the Hobbs Act, which prohibits interfering with interstate commerce by attempting to rob or extort someone. But the case was dropped when a new federal prosecutor picked up the case and decided there was insufficient evidence. The federal government today won't comment.
"The Department follows the facts and the law in making decisions and beyond that, couldn't comment on matters in which no public federal charges were filed," Department of Justice spokeswoman Laura Sweeney said in an e-mail.
The daredevil's widow, Krystal Kennedy-Knievel, said she was unaware of any FBI investigation involving her husband and declined further comment. They were married in 1999.
FBI files are available to the public after the death of their subjects and can provide rare glimpses into the private lives of public figures. For example, former President Ford advised the FBI that two of his fellow Warren Commission members doubted the bureau's conclusion that John F. Kennedy was shot from the sixth floor of the Texas School Book Depository in Dallas, according to his file.
Not all of Knievel's altercations were detailed by the FBI.
Bob Gill, a competitor of Knievel's during the 1970s, said he was part of a confrontation associated with Knievel, but the daredevil later apologized and denied his involvement and the two became friends. Gill was not interviewed by the FBI, but said his run-in mirrored others described in the file. He declined to elaborate.
"I was really, really mad at Evel over the whole thing, but he apologized at least 10 times, and said it was out of his control and I believed him," Gill said.
Gill, who was paralyzed after a failed stunt, said Knievel tried to help him set up a meeting with a doctor who Gill thought would help him walk again. He said Knievel also devised a plan to help pay for the expenses.
"Evel's never done any wrong besides that one little incident," Gill said. "And he's made up for it 1,000 times."