Harley Davidson FLSTF Softail Fat Boy 2016 Service Manual

Harley's own confirmed dealer copy captures the genuine origin story behind this nameplate directly: "when Willie G. Davidson rode the Fat Boy model into Bike Week the first time, let's just say it stopped traffic. No one had ever seen a factory custom motorcycle with this much visual impact before. The look was pure Harley, yet totally new." Autoevolution's own confirmed history debunks a genuine, long-circulated myth about the name: "a false etymology circulated, claiming the name was a contraction of Fat Man and Little Boy atomic bombs dropped on Japan in WW2. However, it proved to be a simple descriptive name" — Harley's own styling and product development VP Scott Miller confirmed in 2015 the name simply describes "the wide appearance when viewed head-on."

Power comes from the High Output Twin Cam 103B, an air-cooled V-twin displacing 1,690cc (103.1 cu in), a 3.87-inch bore and 4.374-inch stroke, a 9.6:1 compression ratio, fed by Electronic Sequential Port Fuel Injection (ESPFI), run through a 34/46-ratio chain primary drive and belt final drive. Eisenhauer's Tioga County Harley's own confirmed factory spec sheet lists gear ratios starting at 9.311:1 in first, 6.454:1 in second, delivering the genuine, strong low-end torque the Fat Boy's signature stance is built around.

That same confirmed dealer specification lists a 31-degree rake with 5.8 inches of trail on a 64.4-inch wheelbase, a 25-inch laden seat height (26.4 inches unladen), and 5.1 inches of ground clearance — riding on 140/75R17 front and 200/55R17 rear tires, wrapped around the model's genuinely signature bullet-hole solid-disc aluminum wheels. Autoevolution's own confirmed styling account details the extensive chrome package that year: "the headlight housing, front fork, engine head covers, cooling fins, bullet-style turn signal housings, exhaust system, and bullet-hole solid disc aluminum wheels."

Fuel capacity comes in at 5 gallons with 3.5 quarts of oil (with filter), and shipped weight sits at 700 lbs (730 lbs in running order) per Harley's own confirmed factory documentation. A range-topping Fat Boy S variant, badged FLSTFBS, ran alongside it that year with a larger 1,803cc engine sharing the same fundamental chassis and styling. This exact FLSTF configuration ran through 2017 before Harley's 2018 Softail platform redesign renamed the model FLFB (107ci) and FLFBS (114ci) on the new single-shock chassis.

This factory service manual covers the procedures, torque specs, and diagrams needed to keep a 2016 Softail Fat Boy FLSTF running the way it was built to.