The DT series was created by Yamaha in the late 1960s when the United States motorcycle market was down. Market research by Yamaha indicated that, despite slow motorcycle sales, there was a largely untapped market for off-road motorcycles. At the time, only a few specialty European manufacturers such as Bultaco and Husqvarna made motorcycles specifically for off-road use. Instead, many owners purchased road motorcycles and modified them for off-road use, typically by raising the muffler, adding braced handlebars, and fitting a bash plate under the engine . Such modifications were commonly known as creating scramblers. The first DT model, the DT-1 trail bike, was released in 1968 and quickly sold out

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