The sound you hear rumbling in the background is not some Fat Boy with after-market slash-cut pipes gliding up alongside you, but rather the maker of that V-twin engine reporting strong fourth-quarter sales and earnings. Harley-Davidson (NYSE:HDI) announced this morning that earnings rose 14% to $209 million on sales of $1.2 billion. That's a lot of Hogs moving off the showroom floor.

Harley's got ambitious plans. It wants to sell 400,000 of its deep-throated, muscular motorcycles by 2007. At current levels, it simply needs to maintain consistent 10%-per-year growth. That appears possible. Last year was the 100th anniversary of the company, and it produced special editions of its bikes that boosted sales. Topping those numbers was no small feat. Last quarter, for example, Harley saw sales come in some 10% below 2003's results even as earnings rose 15% year over year. Still, it's the 19th consecutive year of record profits, and sales topped $5 billion for the first time.

As the sole remaining U.S. motorcycle manufacturer, it competes against the big bikes produced by foreign manufacturers such as Honda (NYSE:HMC). With nearly a 50% market share, Harley sales are undoubtedly also being fueled by the popularity of such TV shows as American Chopper, Biker Build-Off, and Motorcycle Mania. Watching Jesse James or the Teutul family build custom choppers that can run upwards of $50,000 or more inspires purchases.

There's no question a Harley-Davidson commands a premium. While more bikes today are selling at MSRP, suggesting the company is using incentives to dealers to get more motorcycles out the door, there are still enough places where dealers mark up the costs of the bike. You might not face the months of delays waiting for your hog to come in as used to be the case -- heck, Harley pumped out more than 317,000 bikes last year -- but demand for the larger bikes continues to be strong.

Part of that is a new demographic in Harley riders has been gaining momentum: women. No longer the province of bearded, tattooed, leather-jacketed men, women made up 10% of Harley's sales in 2003. The Motorcycle Industry Council says women account for about 10% of all motorcycle sales nationwide.

Gross margins at Harley continue to climb, coming in at 38% of revenue versus 36% last year. Operating margins also increased, up 21% from a year ago. While international sales were strong in the fourth quarter, up 14% against domestic sales increases of 7%, annually revenues came in 7% higher in the U.S., while international sales grew almost 2%. The company plans on offering reduced prices on select European models in 2005.

Free cash flow continues to be strong as well, though at $676 million it's down slightly from last quarter. The company also bought back more than 10 million shares of outstanding stock which are still pricey and trade just a little under their 52-week high. But at 17 times forward earnings and an expectation to ship 339,000 more bikes this year, there just might be room in both your portfolio and your garage for a Harley of your own.

Fool contributor Rich Duprey recently sold his 2003 Deuce and is suffering from withdrawal. He does not own any of the stocks mentioned in this article.