On March 11, 1984, flocks of migrating birds swirled over the Daytona International Speedway, venue for the United States' largest motorcycle race event. This was the Daytona 200-Mile, where competitors vied for the distinction of being called the world's fastest on two wheels.
Intent on a 13th consecutive victory, Yamaha again entered its YZR700 (0W69), which was a square-four rotary disc valve YZR500 modified specially for the Daytona. While the finals became a contest among Kenny Roberts, Eddie Lawson and Freddie Spencer (on a Honda NSR500), Roberts won after remaining in front throughout the race by foregoing a tire change.
Also in the race was Tadahiko Taira, who became the All-Japan 500cc class champion for the first time the previous year. Showing an outstanding improvement from 18th in the preliminaries, he finished 5th after Lawson, who crossed the line in 4th position.
For Taira at that time, however, the experience of doing battle with "King" Kenny Roberts and his likely successor Eddie Lawson was surely more valuable than his 5th-place finish. He admitted this clearly in commenting later: "In my career, that was the race in which I learned the most lessons."
On that same day, at the Suzuka Circuit dusted by light snow flurries, the "2 & 4" race was being held. This ground-breaking event that enable spectators to watch top level domestic four- and two-wheeler racing at the same time resulted from an initiative proposed by riders and race supporters eager to give more people exposure to motorcycle racing. The 2 & 4 was held as the opening round of the All Japan Road Race Championship.
As Taira was away at Daytona, Hiroyuki Kawasaki took over as Yamaha's "GP500 ace." The YZR500 machine entered by Yamaha was the V4 engine 0W76, riding on new vertical-type rear shock absorbers. (During the season, the intake system had been changed from a rotary valve to a crankcase reed valve system.)
With the World GP due to start in two weeks, this model was selected while the final testing was still in progress. But Hiroyuki Kawasaki and the new YZR500 made the strong start Yamaha hoped for and dominated the race from the beginning. Hiroyuki Kawasaki's fine riding continued well past the starting stage and he increased his lead with each lap until he entered the final lap with a considerable advantage.
However, that was when the fate turned its back on him. As he came out of the final corner with its gentle downhill and headed toward the home straight, the spectators saw the YZR500 making a slow descent. His large body packed away tightly behind the cowl, Kawasaki was practically costing as his machine lost power. Before he could roll over to the finish line, two machines ― a Honda and a Suzuki ― swooped past him.
Later he described what had happened. "The cause was engine related. At the time it was really frustrating. The prospect of victory evaporated right in front of my eyes. But a solution was quickly incorporated and we were able to send an improved engine to South Africa for the start of the World GP. That was part of Eddie [Lawson's] first win."
On March 24, Lawson raced in the opening round of the World GP in South Africa. Riding a 0W76 on a rainy Kyalami Circuit, he won his maiden victory, the first of what would eventually be a career total of 31 World GP500 wins.
Also that year, bolstered by technique and know-how handed on from Roberts, Lawson won his first World GP title. Taira, too, won the All Japan Road Race Championship for the second year in a row.
From Roberts and Kawasaki, to Lawson and Taira. Those three races in March 1984 and those four riders graphically illustrated the way in which Yamaha's technology and spirit are handed on.