Across 8 covered model years from 1998 to 2019, the Harley-Davidson Softail Fat Boy motorcycle has supplied wet/running weights ranging from 698.9 lb (317 kg) to 734.1 lb (333 kg) and dry weights ranging from 626.1 lb (284 kg) to 705.5 lb (320 kg), depending on model year.
Harley-Davidson Softail Fat Boy weight overview
This is a very heavy motorcycle. Good footing, sensible parking direction and avoiding awkward slopes make a real difference when handling it at walking speed.
Very Heavy Motorcycle
How heavy is the Harley-Davidson Softail Fat Boy?
wet weight
Using a model-level wet weight comparison, the Harley-Davidson Softail Fat Boy is heavier than about 82.4% of 168 Harley-Davidson custom/cruiser motorcycles with compatible weight data.
Dry vs ready-to-ride weight
Bike + rider total weight
These totals use the model’s representative wet weight. They exclude riding gear, luggage and a passenger.
Harley-Davidson Softail Fat Boy weight & related specs
| Model years covered | 1998, 2013, 2014, 2015, 2016, 2017, 2018, 2019 |
|---|---|
| Wet / running weight | 698.9 lb (317 kg) to 734.1 lb (333 kg) |
| Dry weight | 626.1 lb (284 kg) to 705.5 lb (320 kg) |
| Engine displacement | 1,338 cc to 1,746 cc |
| Power | 56 hp to 78 hp |
| Torque | 73 lb-ft (99 Nm) to 106.9 lb-ft (145 Nm) |
| Fuel capacity | 5 US gal (18.93 L) |
| Full-tank fuel weight (estimated) | 31.1 lb (14.1 kg) |
Weight changes by model year
The 1998 model is used as the baseline where data is available. Only later supplied values that differ are shown below. A year pill does not mean every individual weight field was supplied for that year.
Useful weight calculations
| Horsepower per 100 lb | 8.94 hp / 100 lb to 10.62 hp / 100 lb |
|---|---|
| Pounds per horsepower | 9.41 lb / hp to 11.18 lb / hp |
| Torque per 100 lb | 11.66 lb-ft / 100 lb to 15.3 lb-ft / 100 lb |
| Displacement per pound | 2.14 cc / lb to 2.5 cc / lb |
| Weight per 100 cc | 40 lb / 100 cc to 46.8 lb / 100 cc |
| Fuel weight as % of bike weight | 4.2% to 4.4% |
| Weight with full tank | 701.3 lb (318.1 kg) to 736.6 lb (334.1 kg) |
What the weight numbers tell you
Harley-Davidson Softail Fat Boy weight FAQ
How much does the Harley-Davidson Softail Fat Boy weigh?
For the model years covered here, wet/running weight is 698.9 lb (317 kg) to 734.1 lb (333 kg), while dry weight is 626.1 lb (284 kg) to 705.5 lb (320 kg). Do not treat dry and wet figures as interchangeable.
How does the Harley-Davidson Softail Fat Boy weight compare with similar Harley-Davidsons?
It is on the heavier side. Its representative wet weight is around the 82nd percentile among 168 compatible Harley-Davidson custom/cruiser motorcycles.
Are all Harley-Davidson Softail Fat Boy model years the same weight?
There are year-to-year differences in the supplied data. The earliest covered year is used as the baseline, with later changed values shown separately above.
What does a full tank of gas weigh on the Harley-Davidson Softail Fat Boy?
A full tank works out to about 31.1 lb (14.1 kg) from the listed 5 US gal (18.93 L) capacity. Actual fuel density varies slightly, so treat it as a practical estimate.
What does the Harley-Davidson Softail Fat Boy weigh with a 180 lb rider?
The approximate combined total is 908 lb (411.8 kg) with a 180 lb rider, based on the representative wet/running weight used on this page.
Is the Harley-Davidson Softail Fat Boy strong for its weight?
The calculated range is 8.94 hp per 100 lb to 10.62 hp per 100 lb. This ratio is usually more informative for acceleration comparisons than horsepower alone. That places it around the 50th percentile within the compatible Harley-Davidson custom / cruiser power-to-weight comparison.
How much weight do fuel and fluids add to the Harley-Davidson Softail Fat Boy?
Available years with both measurements show about 28.7 lb (13 kg) to 37.9 lb (17.2 kg) added between dry and ready-to-ride figures. Fuel explains part of it, while oil, coolant and specification definitions can explain the rest.
How much of the Harley-Davidson Softail Fat Boy total weight comes from fuel?
Fuel accounts for roughly 4.2% to 4.4% of the available motorcycle weight figure. On lighter bikes that share can be surprisingly noticeable.
How does Harley-Davidson Softail Fat Boy torque compare with its weight?
Available data gives 11.66 lb-ft per 100 lb to 15.3 lb-ft per 100 lb. That ratio helps explain how strong the engine is relative to the bike’s mass, especially at lower speeds.
Motorcycle specifications can vary by model year, market, equipment and the exact dry/curb-weight definition. Calculated fuel-weight and ratio figures on this page are estimates derived from the supplied specifications. Confirm critical figures in the owner’s manual or on the official Harley-Davidson website.