MXA’S TWO-STROKE TUESDAY: KAWASAKI KX500
The Kawasaki KX500 was (and still is) known as a beast. Kawasaki released their 500 machine in 1983. Yamaha, Suzuki, Honda and Maico already had a production bike in the class at the time, making Kawasaki’s bike quite late (a common trend, given Kawasaki’s late entrance with the KX450F over two decades later). For comparison, the 1983 the 500cc Grand Prix series had already been going on for 31 years. By 1983, the AMA Nationals had been running for 11 years. Kawasaki hadn’t completely ignored the big bike class. The production KX400 two-stroke was a viable competition bike in the class. The first big rider that they put on their powerful bike was Brad Lackey. Lackey would first appear at a main event at Cal-Expo, three races into the 1972 season. While he won his first few races on a CZ, he would switch to a Kawasaki works SR450 before the season ended. In 1979, Lackey landed the brand its first GP win at the 1979 GP of France. Jim Weinert also achieved success on the mighty bike.
The initial SR450 underwent a few changes the first decade. The displacement was lowered to 420cc and the rear suspension featured a single shock with a linkage. With the release of the KX500 in 1983, naturally Kawasaki wanted to put a rider on it. Goat Breker was the man chosen. Goat had been on the Kawasaki team in 1981 and 1982, along with Mark Barnett in 1981. For 1983, Kawasaki had Kent Howerton, but Kent opted to move back to the 250 class once the season was over. Goat Breker would finish third overall and make all but one podium in the 1984 season. Kawasaki intended for the new machine to be a one-off works bike, but the AMA had a different idea. In 1986, they instituted the production rule, which forced bikes to be made out parts available on the market.
The fledgling KX500 wasn’t a favorite by the standards of the mid 1980’s. It was bulky, air cooled, and the engine had flaws. Some even claimed the bike was unridable. Kawasaki was quick to develop a new engine and chassis going into 1985. Also new to 1985 was the engine being water cooled. The changes appealed to riders from a different market–desert racing. 1988 would be the last major change for the bike before it was discontinued almost a decade later. Most motocross racers favored the Honda CR500 for its chassis and the KX500 for its powerband.
Even though research and development stagnated, the KX500 still made the top step of the podium. Ron Lechien dominated the MXDN on the KX500. Jeff Ward would win the 500 AMA National Championship in 1989 and 1990. Mike LaRocco won the last AMA 500 National championship on the KX500. Kawasaki would keep making the machine until 2004 when 500cc two-strokes were no longer considered desirable by consumers. For the average Joe, the KX500 was too powerful. Kawasaki switched their focus to a four-stroke–the KX450F. While the KX500 is rarely seen these days, enthusiasts like Sean Collier keep the legacy of the KX500 machine alive by racing it at the Two-Stroke World Championship, Mammoth Mountain and the World Vet Championship.