2015 Harley-Davidson Road King Technical Analysis & Specification Breakdown
Engineered by Harley-Davidson for the touring motorcycle segment, the 2015 Harley-Davidson Road King relies on a 1688 cc (103 cu in) air-cooled v2, four-stroke powerplant. In factory specification, peak output is rated at 85.8 HP (62.6 kW) at 5,000 rpm while maximum torque reaches 138 Nm (101.8 lb-ft) at 3,250 rpm, transferring power to the rear wheel through a 6-speed gearbox and belt final drive. With a specific output of 50.8 HP per liter and a 1,750 rpm working window between peak torque (3,250 rpm) and peak power (5,000 rpm), the engine character is prioritizing low-RPM tractability, mechanical longevity and relaxed throttle response over peak redline numbers.
On the scales, the Road King measures 367.9 kg (811 lbs) wet (curb), translating to a power-to-weight ratio of 0.23 HP/kg (4.29 kg per horsepower). Rider ergonomics and chassis geometry center around a 678 mm (26.7 in) seat height — giving shorter riders and urban commuters confident flat-foot reach at traffic stops, combined with a 1,613 mm (63.5 in) wheelbase engineered for planted straight-line stability. The 22.71-liter (6 US gal) fuel tank paired with a rated consumption of 5.6 L/100 km provides an estimated theoretical range of roughly 406 km (252 miles) between fill-ups.
Within MotoLibrary's Harley-Davidson archive, this model family spans 13 indexed model years from 1996 to 2022, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.
Specific Output
50.8 HP/L
Power-to-Weight
0.23 HP/kg (4.29 kg/HP)
Power Band Window
3,250–5,000 rpm
Theoretical Range
~406 km (252 mi)
Engine
Displacement1688.0 ccm (103.00 cubic inches)
Engine TypeV2, four-stroke
Engine DetailsAir-cooled Twin Cam 103™ with Integrated Oil-Cooler
Power85.8 HP (62.6 kW)) @ 5000 RPM
Torque138.0 Nm (14.1 kgf-m or 101.8 ft.lbs) @ 3250 RPM
Compression9.6:1
Bore x Stroke98.4 x 111.3 mm (3.9 x 4.4 inches)
Fuel SystemInjection. Electronic Sequential Port Fuel Injection
LubricationDry sump
CoolingAir
Transmission
Gearbox6-speed
Final DriveBelt (final drive)
ClutchMulti-plate with diaphragm spring in oil bath
DrivelineChain, 34/46 ratio primary drive
Performance
Fuel Consumption5.60 litres/100 km (17.9 km/l or 42.00 mpg)
Greenhouse Gases129.9 CO2 g/km. (CO2 - Carbon dioxide emission)
ExhaustChrome, 2-1-2 dual exhaust with tapered mufflers
Chassis
Rake26.0°
Trail170 mm (6.7 inches)
Wheelbase1613 mm (63.5 inches)
Ground Clearance130 mm (5.1 inches)
Wheels & Brakes
Front Tyre130/80-B17
Rear Tyre180/65-B16
Front BrakesDouble disc. Optional ABS. 4-piston
Rear BrakesSingle disc. Optional ABS. 2-piston
WheelsBlack, 28-spoke Cast Aluminum
Dimensions & Weight
Dry Weight355.2 kg (783.0 pounds)
Weight incl.367.9 kg (811.0 pounds)
Power/Weight0.2417 HP/kg
Seat Height678 mm (26.7 inches) If adjustable, lowest setting.
Overall Length2464 mm (97.0 inches)
Fuel Capacity22.71 litres (6.00 US gallons)
Oil Capacity3.80 litres (4.02 US quarts)
Other
StarterElectric
Color OptionsBlack Magic, Deep Jade Pearl/Black Magic, Mysterious Red, Superior Blue, Sunglo/Blackened Cayenne Sunglo, Brilliant Silver Pearl/Vivid Black, Morocco Gold Pearl, Vivid Black, Brilliant Silver Pearl
InstrumentsTank-mounted electronic speedometer with odometer, time-of-day clock on odometer; dual trip meter; low fuel indicator light and mileage countdown feature; low oil pressure indicator light; engine diagnostics readout; LED indicator lights; 6-speed indicator light
LightHigh beam, running lights, front fender running lights, directional light bar, neutral, low oil pressure, engine diagnostics, turn signals, security system (optional), 6-speed, low fuel warning, cruise control (optional), ABS (optional)
Use this page to compare this motorcycle by its real specifications, not only by model name. Focus on the details that affect fit, comfort, handling, range and ownership.
Power
Compare engine output with similar motorcycles if acceleration, highway use or two-up riding matters.
Torque
Torque is useful for judging real-world pull, especially for touring, commuting and loaded riding.
Seat Height
Check the seat height against your inseam and riding posture before choosing a motorcycle.
Weight
Compare weight carefully because it affects low-speed handling, parking and confidence.
Fuel Capacity
Fuel capacity helps estimate touring range and how often you may need to stop.
Brakes
Brake setup is worth comparing if you ride in traffic, mountains or with a passenger.
Transmission
Transmission and final drive affect maintenance, smoothness and everyday usability.
