Jim Knaub, an accomplished athlete who became a wheelchair racing legend, actor and all-around inspiration after a motorcycling accident left him paralyzed from the waist down, has died. He was 68.

Through 25 years of wheelchair racing, Knaub set countless records in the sport, but what his friends and family say left a bigger impact was his enduring message as an activist and speaker for people facing challenges: Despite life’s pitfalls, just keep going.

His credo was, “Why walk when you can fly?”

Born in Corona and raised in Lakewood, Knaub died earlier this month in his longtime hometown of Long Beach. His family said his cause of death is still yet to be known.

Knaub started his athletic journey as a pole vaulter at Cal State Long Beach, but after his accident left him unable to walk, his life shifted and he became one of the world’s best-ever wheelchair competitors.

“Jim was a man who never allowed adversity to define him,” wrote his brother, Fred. “His legacy is not only in his medals and records but also in the countless lives he touched through his courage, determination, and unyielding positivity. He inspired all who knew him to approach challenges with strength and grace, proving that life’s most significant victories come not from avoiding hardship but from facing it with an open heart.”

James “Jim” William Knaub was born on Jan. 5, 1956, in Corona to George and Leola Knaub. He was born minutes after his twin sister, Debra Cathleen Knaub. Jim Knaub was raised in Lakewood alongside his twin and other siblings, Cheryl, Fred and Stanley Knaub.

Jim Knaub’s athletic journey began when he competed as a pole vaulter at Cal State Long Beach. He reached the semifinals of the 1976 U.S. Track and Field Olympic Trials.

In 1978, a motorcycle accident ended those Olympic pole vault dreams. But they didn’t end his athletic career. Not by a long shot.

Two years after his accident, Jim Knaub took up wheelchair racing. And many say he single-handedly transformed the sport and how its athletes are perceived.

While winning race after race, he brought his dynamic personality and flair to the competition and raised the sport’s profile at the same time, his family wrote in his obituary.

He won the 1982 Boston Marathon and went on to win it four more times. He won the Los Angeles Marathon three times, and the Long Beach Marathon 11 times.

Jim Knaub won myriad other races around the world as well. By the 1990s, he had set every wheelchair racing world record possible, his family said, from the 5K to the marathon.

“I wasn’t sure how far it would take me, but I knew it was something I wanted to try,” Jim Knaub wrote in a fundraising campaign in 2022.

Jim Knaub became an inspirational speaker, giving talks at recovery centers for paraplegics, quadriplegics and people who had just endured accidents.

“He’d go in there and tell them, ‘Hey, I’m not here to tell you what you can’t do but I’m here to tell you what you can do,’ ” his brother Fred Knaub said. “He spent a lot of time helping people get outside and do stuff.”

When Jim Knaub was presented with medals and trophies, he would look out among the crowd to find a young person who had a disability, or anyone he thought would benefit, and give away such honors, said Dan Gooch, a past president of the Long Beach Century Club and a close friend of Jim Knaub.

“When he gave them away, he told the young person that if he could overcome what he did and accomplish what he did, then the young person could do the same,” Gooch said in an interview. “He was an inspiration to many, many, many young people and to anyone that knew him.”

Jim Knaub was a member of the Long Beach Century Club. In 1980, he was awarded one of the group’s most prestigious honors, the Hank Hollingworth Award. The next year in 1981, he was named Athlete of the Year.

In 2019, Jim Knaub was inducted into the club Hall of Fame.

“Of the more than 60 years of the Century Club, he is one of the few individuals that has received both the Athlete of the Year and named to the Hall of Fame,” Gooch said. “He was an outstanding athlete and a better person.”

Jim Knaub was also selected for the Lakewood Youth Hall of Fame in 1981, and the Cal State Long Beach Hall of Fame in 1990.

Bob Babbitt, co-founder of Competitor Magazine and the Challenged Athletes Foundation, shared a tribute message for Jim Knaub on social media, saying that his impact on the wheelchair racing sport, and “on living life to the max,” will be felt forever.

“Jimmy was a true trailblazer,” Babbitt wrote. “In the late ’80s and early ’90s, Jim changed the way many people thought about someone in a chair.”

Beyond athletics, Jim Knaub was also an actor, appearing in TV shows such as “Airwolf,” “The A-Team,” “The Love Boat” and “Happy Days.” A movie about Jim Knaub’s life, titled “Hell on Wheels,” is in development, his brother confirmed.

In later years, Jim Knaub’s passions extended to environmental causes and he started a fundraising campaign, The PCH Cleanup Project, to encourage people to spend time outdoors and to promote environmental stewardship.

Friends and family say he always had a smile on his face.

Jim Knaub, who died Nov. 18, was preceded by his parents and brother Stanley Knaub. He is survived by his siblings Debra, Fred and Cheryl Knaub, as well as numerous nieces and nephews.

“Jim’s life was a testament to resilience, strength, and the power of the human spirit. He will be deeply missed but forever remembered,” Fred Knaub wrote.

Jim Knaub’s family and friends are in the process of planning a celebration of life, details of which are to come.