Japan's Yamaha Motor Co. announced Wednesday a net loss of about 1.8 billion dollars for the nine months to September due to sluggish motorcycle sales, a stronger yen and restructuring costs.

The company posted a net loss of 158.76 billion yen (1.76 billion dollars) for the first three quarters of 2009, against a year-earlier profit of 43.15 billion yen.

It booked an operating loss of 44.97 billion yen, against a profit of 64.08 billion yen in the same period of the previous year. Revenue plunged 33.1 percent to 858.51 billion yen.

The bottom line was hit by a one-off loss of 73.5 billion yen due to restructuring costs such as asset impairment charges and early retirements.

Sales at Yamaha's mainstay motorcycle business dropped 26.6 percent due to weak demand in Europe, the United States and Brazil, which offset solid sales in Asia, the company said.

For its full business year through December, Yamaha maintained its forecasts for a net loss of 182 billion yen, an operating loss of 87 billion yen and revenue of 1.1 trillion yen.

Yamaha had been enjoying record sales until the economic crisis hit demand for its products, which also include boat engines and all-terrain vehicles.