For 2011, Harley-Davidson offers two types of Fat Boy motorcycles. The Fat Boy Lo differs from the Fat Boy in that the bike has a lower seat. They both share engine and basic chassis details, but the Fat Boy Lo is visibly lower to the ground.
The 2011 Fat Boys have a twin cam 96B engine of 96 cubic inches displacement that is air-cooled and has a bore and stroke of 3.75 inches by 4.38 inches. The compression ratio is 9.2 to one. The fuel system uses electronic sequential-port fuel injection.
The Fat Boy is 94.3 inches in length, has a wheelbase of 64.5 inches and a trail of 5.8 inches. The fuel tank holds 5 gallons and the oil capacity is 3.5 quarts. The Fat Boy Lo has a ground clearance of 4.8 inches compared to the usual 5.1 inches. The Lo also weighs six pounds more, at 700 pounds, than the Fat Boy does. The Lo’s seat height is at 26.35 inches compared to the Fat Boy’s 27.5 inches.
The Fat Boys have a fuel economy of 35 mpg in the city and 54 mpg on the highway. The engine produces 93.7 foot-pounds of torque for this classic cruiser.