Strong sales of off-road vehicles and Victory motorcycles continue to help Polaris Industries Inc. buck weak industrywide demand for recreational vehicles, boosting the Medina-based company's third-quarter earnings 51 percent and sales 33 percent.

On Tuesday, the company posted earnings of $47.2 million, or $1.37 per share, for the quarter ended Sept. 30. Sales for the period totaled $580.1 million.

Results topped estimates by analysts, who forecast earnings per share of $1.14 and sales of $522.1 million.

"We gained market share in every product line in North America and in our international markets," CEO Scott Wine said in a conference call with analysts.

Polaris said it now expects full-year 2010 earnings per share to be in the range of $4.17 to $4.20, a marked improvement over 2009 results of $3.05 per share. Sales for 2010 are now expected to grow in the range of 24 to 25 percent over 2009 sales of $1.57 billion.

Off-road vehicles and motorcycles are expected to fuel most of the growth for the rest of the year. Snowmobile sales should have a double-digit seasonal gain in the fourth quarter but will be flat for the full year.

Polaris shares rose about 4 percent Tuesday, closing at $72.34. Volume was more than three times the recent daily average, with about 1.5 million shares changing hands.

Side-by-side vehicles, which allow a passenger to sit next to the driver, fueled most of the 49 percent increase in sales of off-road vehicles in the third quarter and offset soft sales of core all-terrain vehicles. The segment is Polaris' largest, accounting for about two-thirds of total sales.

Company officials credited new products and a program that allows shorter ordering cycles for dealers. Polaris also continues to build its military-related off-road business and on Tuesday announced a contract valued at up to $67 million to provide utility vehicles to the Army National Guard.

Sales of Victory motorcycles more than doubled to $20.1 million. Sales of parts, garments and accessories rose 12 percent to $93.3 million, while snowmobile sales declined 6 percent to $77.3 million.

Susan Feyder • 612-673-1723