Harley-Davidson started shipping the Street series to select countries in the first quarter. Image source: Harley-Davidson.

Shares of Harley-Davidson (NYSE:HOG) revved up a 6.7% gain in pre-market trading, following the release of the motorcycle maker's first-quarter results. The stock is setting new multiyear highs on the news.

Sales increased 11% year over year to $1.6 billion. Diluted generally accepted accounting principles earnings rose 22% to $1.21 per share. Analysts has been looking for earnings of $1.08 per share on about $1.5 billion in revenue.

The company reported $178 million in positive free cash flow, up from negative $131 million in the year-ago period. Harley shipped 80,682 motorcycles in the first quarter, a 7.3% year-over-year improvement.

The average selling price per bike worked out to $16,175 in the quarter, up from $15,339 in the year-ago period.

Looking ahead, management expects to ship 92,000 to 97,000 motorcycles in the second quarter, up from 84,606 units in the second quarter of 2013. Full-year guidance remained steady at roughly 8% year-over-year unit growth.

Harley-Davidson CEO Keith Wandell likes the diversity of Harley's strong sales.

"Together with our dealers, we continued to expand the appeal of our products and the Harley-Davidson experience," said Wandell in a prepared statement. "Harley-Davidson dealers sold more than four times as many new, on-road motorcycles, 601cc and up, to U.S. young adults last year, and among riders age 35-plus, more than nine times as many to women, more than six times as many to African Americans and more than seven times as many to Hispanics, as the nearest competitor."

Anders Bylund has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days.

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