Softail Fat Boy. The 2012 Harley-Davidson Softail Fat Boy FLSTF is one of the quintessential cruiser motorcycles. Hearkening to the "hardtail" choppers of the '60's and '70's, he Harley-Davidson Fat Boy motorcycle keeps that heritage alive more than forty years later. The FLSTF Fat Boy is the original "fat custom" bikeâlaid-back and luxurious with an unmistakable profile on the road. New for 2012, he Harley Fat Boy features a new, arger air-cooled Twin Cam 103 Harley engine with 6-speed cruise drive transmission, roviding more power for passing, ill-climbing, nd riding with passenger and luggage. Take a seat on this Harley and get the experience of one of the 2012 Harley cruiser motorcycles.