Yamaha produced the enduro DT1 250 in 1968. The motorcycle was embraced and Yamaha learned that, in America riders were interested in motorcycles which could operate off-road, and on road. Yamaha experimented with larger displacement and in 1975 they created the DT400B. The DT400B did not initially sell well, and Yamaha reduced the price. The 2 stroke engine was not ideal and by 1979 the DT400B was discontinued.