It appears you're interested in specifications for the Harley-Davidson Softail Fat Boy. This Custom / cruiser model is powered by a Air-cooled, Twin Cam 103B™ V2, four-stroke engine with 1687.97 ccm (103.00 cubic inches) of actual displacement before 9.6:1 compression. Fueling is metered via Injection. Electronic Sequential Port Fuel Injection (ESPFI) allowing this machine to produce its horsepower and 133.84 Nm (13.6 kgf-m or 98.7 ft.lbs) torque. According to our records engine heat of the Harley-Davidson Softail Fat Boy is moderated by Air. You'll need to get familiar with the 6-speed transmission and pay attention to final drive Belt maintainence. Our best information shows that the front tire size is 140/75-R17 and the rear is 200/55-R17 . The entire package is supported by the frame, . We know you like to go fast or cruise all day, but when you need to stop, you'll be dependant on Double disc. 4-piston front brakes and Single disc. 2-piston rear brakes. The Harley-Davidson Softail Fat Boy was launched in 2013, and we're happy to know (or assume) you've got one in your garage. To help you keep your ride in tip-top shape, consider purchasing an owner or service manual.