VOL.212 FEBRUARY 2026
CYCLING JAPAN The History of the Mass Production of Electrically Power-Assisted Bicycles, Pioneered by Japan

The first model of the PAS electrically power-assisted bicycle, released in 1993
Photo: Yamaha Motor Co., Ltd.

Japan led the world in the mass production of the electrically power-assisted bicycle, which uses a motor to assist the rider’s pedaling and make riding easier. We interviewed a representative of the manufacturer about the development and technological background behind the electrically power-assisted bicycle designed for hills and urban areas.

Bicycles have become deeply rooted and widespread in everyday lives as convenient vehicles that support daily transportation. The advent of the electrically power-assisted bicycle triggered a major evolution for the bicycle. Yamaha Motor Co., Ltd. was the first company in the world to sell such bikes, and ISHII Kenji, who has been involved in the company’s electrically power-assisted bicycle business for many years, recollects. “In the late 1970s, environmental and energy issues began drawing attention as challenges to Japanese society. As a motorcycle manufacturer, we also conducted research on environmentally conscious mobility solutions.”

By the late 1980s, about 60 million bicycles were already in use in Japan. While many people used bicycles as a means of everyday transportation, many urban and residential areas in Japan are hilly, and slopes have posed a major barrier to the use of bicycles for commuting, shopping, and carrying loads. This led to the idea of adapting bicycles to better suit Japan’s terrain and lifestyle, making them easier to ride on slopes. Yamaha believed that if technology could assist with hills—considered a weakness of the bicycle—then a wider range of people could utilize bicycles in more situations.

These ideas led Yamaha in 1988 to begin full-scale development of the Power Assist System, which detects a rider’s pedaling force and uses a motor to support it according to the strength applied. However, it was not easy to achieve a natural harmony between the rider’s pedaling power and the motor’s assistance. ISHII says, “We had to make it detect the rider’s pedaling force and control the motor to respond smoothly according to its power. A jerky response would make the rider feel uncomfortable.”

After much trial and error, PAS, the world’s first mass-produced electrically power-assisted bicycle, was born in November 1993. The name PAS stands for Power Assist System. The product was first released on a limited basis in  Kanagawa, Shizuoka, and Hyogo Prefectures. After the product’s effectiveness was verified, it went on sale nationwide the following year (1994). “When PAS went on sale, it was mainly used by elderly people,” ISHII recalls. “I think they saw the value in being able to ride on hills safely and comfortably even with their reduced physical strength.”

In the late 1990s, prices fell as improvements in battery performance and other technologies, economies of scale from upgraded production techniques, and rising sales took effect. As a result, electric power-assisted bicycles became more widely adopted in households. In 1997, awareness increased further through TV commercials, which drove up demand, especially among mothers. From the 2000s onward, the product took root in daily life, with expanded variations tailored to specific uses, including child-carrying models that enable children to ride in front and/or in back, as well as models for commuting and shopping.

“When we began development, we never imagined that parents would one day come to use electrically power-assisted bicycles for their children’s daily drop-offs and pick-ups for kindergartens and nursery schools,” says ISHII. “As one of those involved in this work, seeing how useful they are to people’s everyday lives gives me a strong sense of accomplishment.”

The technology behind electrically power-assisted bicycles has also spread overseas. The use of eBikes¹ has grown in Europe particularly, mainly for daily urban commutes and leisure, thanks to its foundational technology: the electrically power-assisted bicycle expertise cultivated in Japan.

“Three years after the PAS entered full-scale nationwide commercial sales, in 1997, we began to supply power units for electrically power-assisted bicycles to Europe. These were installed on locally-made bicycles, and sales began of electrically power-assisted bicycles equipped with Yamaha-made power units manufactured in Japan. Later, as the product caught on, the term “eBike” was born, and a Japanese technology became established as part of an overseas product.”

Today, electrically power-assisted bicycles are no longer just for everyday use by mothers and the elderly. Their practical applications range from commuting to work and school, to sports and outdoor activities, as well as convenient rental bikes for sightseeing in towns and cities. ISHII shares his outlook for the future: “We want to continue to offer new concepts for electrically power-assisted bicycles that go beyond practical and leisure uses.”

• 1. The term used to describe a type of electrically power-assisted bicycle. It usually refers to sports-type bicycles equipped with a motor.

By TANAKA Nozomi
Photo: Yamaha Motor Co., Ltd.