Yamaha MX100 Dirt Bike (1974-1983)

The Yamaha MX100, produced from 1974 to 1983, was a 97cc two-stroke off-road motorcycle designed primarily for junior motocross competitors. This air-cooled, single-cylinder machine consistently featured a 97cc engine throughout its production, delivering 16 bhp from 1974 to 1980. It was offered as a single "Base" model each year, with annual letter suffixes (e.g., MX100A, MX100K) indicating the model year rather than distinct trim levels. A significant redesign marked the 1974 model year. This update introduced a true motocross frame with a lower center of gravity, a new lightweight front hub, a center muffler, longer travel front forks, and Thermal-Phase rear shocks. The 1974 MX100 also incorporated Yamaha's Torque Induction reed valve intake system to improve low-RPM horsepower, alongside a new expansion chamber/silencer for reduced noise. While the core engine remained constant, continuous minor refinements were made throughout the 1974-1983 period. FAQ:

Q: Is this product compatible with my Yamaha MX100?

A: To ensure compatibility, please use the year and model selector at the top of this page.

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