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Roberts Ruined This Man’s Career
Former World Champion Kenny Roberts is known for many things—being America’s first 500cc Grand Prix road-racing champion, an AMA Grand National Champion, three-time Daytona 200 winner and owner of the rare Grand Slam in AMA racing. One thing Roberts is considerably less known for is for being the man wh
o brought on the ruination of Keith Mashburn’s racing career.
Mashburn was Yamaha’s up-and-coming young AMA Grand National rider in the early 1970s. As a full-time Yamaha employee, Mashburn tested prototype street bikes by day and competed on prototype race bikes on the weekends. It was a good life for the fast kid from Simi Valley, California, but it all ended abruptly when an even younger and inarguably faster kid from Modesto, California—named Kenny Roberts—came on the scene.
When Roberts moved to the expert ranks in 1972, and started winning right off the bat, it became obvious where the factory was going to put its primary efforts. Mashburn was relegated that year to more or less being the guinea pig rider for the factory, testing and helping to perfect the machines that Roberts would eventually win on.
Despite being overshadowed by the new young gun, Mashburn wasn’t totally unhappy about his situation. He was still getting to race all over the country and he’d turn in an occasional great ride, especially if the tracks were rough.
“I knew Kenny was a special talent,” Mashburn said. “But I was faithful to Yamaha. They were the ones who gave me my first big break and I was happy to go along with the program.”
After Roberts’ impressive rookie expert season, teams came calling. If Yamaha wanted to hold on to the best prospect in AMA racing for the 1973 season, they were going to have to pay, and pay big.
“Kenny had a manager, and no one back then had managers,” Mashburn said. “With his talent and a manager, he was able to secure a major portion of Yamaha’s total racing budget. Yamaha decided to eliminate its existing team and form this new one with Roberts and give a little help to Don Castro. I found out I’d lost my ride in Cycle News. I told Yamaha they were crazy for putting their eggs all in one basket, but obviously it turned out to be the best thing they could ever do. It was amazing how incredibly good Kenny was.
“And, of course, that happened to be the same year BSA and Triumph stopped having a factory racing team, and I had turned down an offer from Harley a year before, so there was no chance to go out and pick up a last-minute factory ride.”
Mashburn emerged from the burgeoning scrambles and TT racing scene as a young rider in the mid-1960s. He became a Bultaco factory-backed rider and won a slew of District-37 races in various disciplines. He was so good that he actually beat Roger DeCoster, Joel Robert, Dave Bickers and the rest of the European stars in an early 125cc motocross race at Castaic Park.
“Cycle News had a $100 reward at that time to the first American who could beat the Europeans,” Mashburn remembers. “The 125 class really didn’t get any respect back then, and they told me they meant it had to be in the 250cc class. So that’s one of the claims to fame I never got credit for.”
Yamaha recognized the talent of young Mashburn and hired him to race its new DT-1 in TT races at Ascot Park, where he may have earned the dubious distinction of becoming the lowest paid factory rider of all time.
“I was paid $20 per race, and they would match the purse up to $20,” Mashburn says with a laugh. “So, the maximum I could get from Yamaha was $40 per race. But I was 18 years old, and I had factory leathers, and all I had to do was show up at the track. They gave me the best tuner in the world in Dennis Mahan.”
The Mahan and Mashburn relationship didn’t get off on the right foot.
“In retrospect, as good of a tuner as Dennis was, he was probably a little put off by the fact that he was building bikes for a novice,” Mashburn says. “I told him I wanted a pillion pad put on the rear fender and he said no. I told him that I was the rider, he was the mechanic, and I wanted a pillion pad. He said the bike was designed for the rider to stay in one place. I told him I wanted a pillion pad and he said, ‘Well then, you aren’t going to ride this bike.’ So, I didn’t get a pillion pad.”
Riding Mahan-tuned bikes, Mashburn was nearly unbeatable as a novice. He even beat the experts at the short-track program in Daytona.
Yamaha hired Mashburn as an R&D test rider where he worked with Don Dudek. He tested prototype Yamahas in the vast desert around Las Vegas to keep things top secret.
“We’d get back to hotel in the evenings and the Japanese engineers would head off to the casinos and leave the underage guys like myself behind,” Mashburn recalls.
One of the bikes Mashburn tested was Yamaha’s first four-stroke, the XS-1, a 650cc vertical twin. In 1970, he rode the XS-1 to its debut victory in a Yamaha Gold Cup race at Ascot Park.
“That first race bike was actually built from top to bottom by Ray Hensley of Trackmaster,” Mashburn said. “I never rode the bike until it was delivered to the track by Ray the night of the event. Shell [Thuet] later built a road-racing version of the 650, and being Mr. Loyal, I agreed to ride it at Daytona. The bike tore itself apart after just a few laps.”
Mashburn discovered early on that road racing was never going to be his forte.
“I used to see how quick I could get through the fast left-hand kink in the infield at Daytona as a guide to how well I was catching on to road racing,” he says. “One day in practice, I went through there and thought I was really hauling ass. ‘Now I’m starting to get this,’ I thought to myself. Just then Dave Smith went around me on the outside and tapped me on the shoulder.”
Mashburn scored six top-10 AMA Grand National finishes his rookie season, including a podium on the Terre Haute (Indiana) Half Mile.
At another race, a chain broke on his bike in one practice session, and he ran hard into the back of Bart Markel as he was freewheeling into a turn.
“I’d heard all the stories about ‘Black Bart’ and his boxing career and what he’d done to people,” Mashburn said. “I decided walking back to my pits to keep my helmet on in case he came over to punch me. I walked around with the helmet on for the longest time. I finally took it off and worked up the courage to go over to his pits to explain to him what happened. He was sitting there and looked up at me and said, ‘If I was going fast enough, you wouldn’t have been able to run into me.”
Ultimately racing many of Yamaha’s prototype machines often hurt Mashburn’s results over the course of the following two seasons.
“Whenever Yamaha wanted to test something, I was the first one to raise my hand,” he said. “The result was a lot of DNFs as Yamaha tried to perfect its new four-stroke against the more established Harley-Davidsons.”
After being dropped by Yamaha, Mashburn made a half-hearted attempt to stay in racing in 1973, but when someone offered him decent money for his Triumph race bike, he jumped on it. It was tough for Mashburn to race as a privateer after four years as a factory rider.
Mashburn went on to become a fire investigator and totally walked away from motorcycling for over a decade. It was Skip Van Leeuwen who encouraged him to come back and be a part of the sport that had been such a big part of his life. CN
Monday, October 4, 2021 at 8:14PM