In 1959, Yamaha began development of a factory racer with the intent of entering the World GP. At the same time, the company was participating actively in the domestic race scene that had begun to develop from the Mt. Fuji Ascent Race and the Asama Highlands Race.
The machines used in these races were still race modifications of Yamaha's 250cc YD-1 or YDS-1 production models. With the completion of Yamaha's first RA41 (125cc) and RD48 (250cc) factory racers in 1961, however, the feedback from their development contributed to the simultaneous development of two new sport models. One was the street-legal sport model YDS-2 and the other was the production racer TD-1 targeted at enthusiasts who entered amateur races.
Sporting a distinctive red fuel tank, the TD-1 mounted the same 2-stroke air-cooled 2-cylinder engine as the YDS-2 on a double cradle type frame. It also featured race-spec cylinders, cylinder head, carburetor and muffler as standard equipment. In short it was designed with a level of performance that was race-competitive as it came in its production spec.
When advance export sales of the TD-1 began in the spring of 1962, the reception was even better than expected. It proved very competitive on the track as well, winning competitions like the Malaysia GP, in the hands of a local rider. In July of that year Minoru Mitsuhashi rode the TD-1 to a Japanese debut win in the 5th All Japan Clubman Race held at Gannosu in Fukuoka Prefecture. Then, in November, Mitsuhashi and Yoshimi Katayama rode the TD-1 to a 1-2 finish in the Novice 250cc class of the 1st All Japan Road Race, which attracted more than 30 thousand spectators over two days at the new Suzuka Circuit.
The fact that Japan's race authority at the time, the MFJ (present Motorcycle Federation of Japan), only allowed street-legal production models in its race competitions, meant that Yamaha released the TD-1 in Japan as a fully street-legal model*1 with headlight, taillight and turn signals as standard equipment. At the same time, Yamaha contributed to the development of road racing around the world by releasing the export model TD-1A completely assembled with cowling and a full set of other race parts. This export model was later developed into the TD-1B and TD-1C and became the dominant force in the 250cc class of the USA'sDaytona 100 Mile*2. This success cemented the reputation of the TD series production racers.
Meanwhile, as regulations were changed in the World GP to restrict the number of cylinders and transmission gears on race machines beginning in 1969, the Japanese makers that had been competing with multi-cylinder engines and transmissions with large numbers of gears, began to withdraw from GP competition one after another. Yamaha was no exception. Even though Yamaha ended its factory race program, it continued to support the remaining privateers in the World GP by selling the new TD-2 production racer as the successor to the TD-1, plus the TR-2 for the 350cc class.
The performance of these Yamaha production racers continued to rival the factory machines, as proved by Swedish rider Kent Andresson, who won two GP250 races in the 1969 series on the TD-2. That year, Andersson took the title race with Kel Carruthers on the 4-cylinder Benelli factory machine down to the final round of the season and eventually ranked 2nd on the year. The following year, Rodney Gould rode another TD-2 to claim the GP250 championship title. With successes like this, the number of users choosing the TD/TR series models grew rapidly. With the appearance of the new series models TZ350/250 and the 125cc TA125 in 1973, these Yamaha production racers became the most popular machines in the World GP.
These models established the reputation of "Yamaha the 2-stroke maker" among motorcycle fans worldwide and became legendary machines that race fans still talk about today.
*1: The ban on specialized race machines ended in 1972
*2: Yamaha production racers of the TD/TZ series won 13 consecutive titles from 1965 to 1977