Development on snowmobile technologies began in the spring of 1965.

Yamaha first bought a snowmobile made by the Canadian company Bombardier as a sample and initiated development after thoroughly disassembling and studying it. The company completed a prototype of the YX15 in the summer of 1965. Much effort was put into adopting double tracks in order to improve the handling stability. Immediately thereafter, in midsummer, the Nakatajima Dunes facing the Sea of Enshu were used as a “snowfield,” and running and strength tests were conducted. Tests were also conducted in Tateyama, Shigakogen, and other snowbound regions, and after various problems were overcome, plans were made to test the model in February 1966 in North America, the birthplace of the snowmobile.

First test of the original YX15 prototype at the Nakatajima Dunes

Over a period of about three weeks, the development team traveled to Toronto, Ottawa, Quebec, and other locations, but the results were disastrous. The front part of the snowmobile was too heavy, causing it to sink into the snow. One local test rider ridiculed the product, remarking, “This isn’t a snowmobile, it’s a snow submarine.” But that wasn’t the only criticism. In order to ensure stability, the engine was incorporated into the frame to lower the center of gravity, but test riders complained that “the operator can’t enjoy the acrobatic fun of using his body to maintain balance when cornering” and “there’s no real pleasure with a snowmobile that’s too stable,” so this approach was abandoned.

With the failure of the prototype, the production schedule, which had already been determined, was immediately canceled, and development went back to square one. Other twists and turns were encountered thereafter, but corrective measures were applied in each case and, in the fall of 1967, production finally began on 300 developmental models. The results of trials in various regions of North America were not encouraging, but, by clearing technological hurdles one by one, the product steadily approached the level of quality required by the market. Finally, in July 1968, Yamaha introduced its first snowmobile, the SL350, to the market.

Introduction of Yamaha’s first snowmobile, the SL350 (July 1968)

At first, however, there were numerous complaints out of North America. When decelerating on a down slope and attempting to corner, the tracks would slacken, making it difficult to corner smoothly. The engine was also regarded as lacking sufficient power, and the steering skis would break. In response to these complaints from customers, the running test group resided for an extended time in Shibetsu, Hokkaido, where they worked to solve the problems using a vacant part of the airport there as a test track.

Yamaha bolstered the development organization for snowmobiles in May 1969 and three new models were successively launched on the market. These models earned hard-won praise from North American customers. It had taken four years, but snowmobile development at Yamaha was finally fully underway.

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