Who ever said a company starting its second century in business should add up to a geriatric outlook? Despite recent nervousness over whether Harley-Davidson's (NYSE:HDI) successful centennial push last year had flooded its growth engine, the stock motored to a new 52-week high today when the company more than delivered second-quarter earnings.

Harley's second-quarter earnings motored 22% higher to $247 million, or $0.83 per share, with a much-better-than-expected 8.9% boost in sales to $1.33 million. Analysts had expected the motorcycle maker to earn only $0.75 per share.

As has been the case with lots of luxury goods, after a protracted period of recession -- and the subsequent repression of those consumer impulses -- it seems lots of folks had pent-up cravings. In this case, those cravings were for brand-new Harleys to enjoy some summer fun on the roads. The company cited hyper floor traffic in its dealerships and interest in the company's Sportster, which has been redesigned for 2004.

Going forward, the appetite for Harleys could even extend beyond Baby Boomers and young thrill seekers. Rick Munarriz recently reported that Harley plans to take the high road to China. He pointed out there are plenty of roads in the world for Harley to rule.

Harley, with its loyal following that has built its very solid brand, sort of proves you just can't get a cult stock down; buy-and-hold investors who climbed onto Harley years ago must be happy campers these days. However, it's always tough for prospective investors to figure out a point to jump in.

Here at the Fool, we laud companies that include their cash flow statements with earnings, and Harley has that habit down pat. We also like to focus on companies that grow free cash flow, so that's a metric to watch; free cash flow indicates a company's ability to generate and hold on to cash.

For the first six months of this year, Harley's free cash flow increased a mere 3% from the same period last year, with net income growth of 16.3% outpacing it. Another element to keep an eye on going forward is that when isolating free cash flow growth for the second quarter alone, Harley's FCF actually dropped 19% compared with the same period last year.

Even with today's spike in stock price, Harley shares are trading at a P/E of 25, the usual premium attached to the stock. Investors are betting that that's not too high a price to pay, considering the company continues to show that its appeal remains fresh with buyers.

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What do you think of Harley's earnings and share-price run-up? Talk it over with other Harley-loving Fools on the Harley-Davidson discussion board.

Alyce Lomax does not own shares of any of the companies mentioned.