Harley-Davidson's shares tumbled Tuesday after the company released earnings that showed a double-digit drop in U.S. sales and shrinking market share during the third quarter.

Motorcycle sales slid 13.3 percent in the U.S. from the same time last year, leading to a global sales drop of 7.8 percent. The decline was partially offset by a 2.6 percent bump in international bike sales, which also helped Harley beat Wall Street revenue and profit estimates.

"U.S. retail was down 13 percent. The industry is down 10 percent. So not only did they decline double-digits, they lost share," Raymond James analyst Joe Altobello told CNBC.

Harley's stock tumbled by as much as 6.7 percent to a 52-week low of $36.15 in morning trading Tuesday. It has fallen by almost 24 percent so far this year, closing at $38.73 a share Monday. The company has struggled to gain traction with younger riders in recent years. Even baby boomers are starting to trade in its traditional "Hogs" for lighter motor bikes, analysts say.

The third-quarter earnings beat Wall Street expectations as the company reduced expenses and boosted international sales, sending profit surging 67 percent to $113.9 million.

The company earned 68 cents a share during the quarter, compared with 53 cents a share projected by analysts in a Refinitiv survey.

Revenue was $1.32 billion, compared with $1.15 billion a year earlier. Analysts had expected the company to generate $1.07 billion in revenue.

"As we manage our business with resilience in a challenging time in our history, we are leveraging our strengths for a more promising road ahead," said Matt Levatich, president and CEO. "We are investing to build the next generation of Harley-Davidson riders and we are optimizing our business to drive profitability and cash flow."

The company continues to expect to ship 231,000 to 236,000 motorcycles total in 2018, with about 45,800 to 50,800 shipping in the fourth quarter.

Levatich rolled out an aggressive "more roads to Harley" growth plan in July that includes an expanded lineup of lighter motorcycles, smaller urban retail stores, a new digital strategy and an international push as U.S. sales fall.

The Wisconsin-based company plans to launch by 2020 a new platform of 500 cubic centimeters to 1250 cc middleweight bikes and an even smaller bike for emerging markets in Asia. The biggest Harley engines run at around 1,700 cc and weigh more than 1,000 pounds — making the new lineup a significant departure from its Hogs.

The company came under fire from President Donald Trump during the quarter. He criticized Harley after it announced plans in June to move its European market production out of the U.S. because of retaliatory tariffs from the European Union.

BMO Capital Markets said Hogs have fallen out of favor with riders, who are trading them in for Indian motorcycles, another heritage motorcycle brand owned by Polaris and one of Harley's main competitors.

Separately, Harley-Davidson said it is issuing a voluntary recall for a hydraulic clutch assembly on all model year 2017 and 2018 Touring, Trike, and CVO Touring models as well as some 2017 Softail models. The recall affects about 238,300 motorcycles worldwide and will cost the company about $35 million.

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