FLSTFI Fat Boy

2003 Harley-Davidson FLSTFI Fat Boy Technical Analysis & Specification Breakdown

Positioned in Harley-Davidson's custom - cruiser motorcycle lineup, the 2003 Harley-Davidson FLSTFI Fat Boy utilizes a 1449 cc (88.4 cu in) air-cooled v2, four-stroke layout. In factory specification, maximum torque reaches 105 Nm (77.4 lb-ft) at 3,000 rpm, transferring power to the rear wheel through belt final drive. Internal engine geometry specifies a bore and stroke of 95.3 x 101.6 mm (3.8 x 4.0 inches) with a 8.8:1 compression ratio.

On the scales, the FLSTFI Fat Boy measures 320 kg (705 lbs) dry. Rider ergonomics and chassis geometry center around a 699 mm (27.5 in) seat height — giving shorter riders and urban commuters confident flat-foot reach at traffic stops, combined with a 1,630 mm (64.2 in) wheelbase engineered for planted straight-line stability. The 19.7-liter (5.2 US gal) fuel tank supports practical everyday commuting and weekend road stints.

Within MotoLibrary's Harley-Davidson archive, this model family spans 4 indexed model years from 2002 to 2006, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.