Engineered by Harley-Davidson for the custom - cruiser motorcycle segment, the 2006 Harley-Davidson FLHRSI Road King Custom relies on a 1442.2 cc (88 cu in) air-cooled v2, four-stroke powerplant. In factory specification, maximum torque reaches 116.6 Nm (86 lb-ft) at 3,500 rpm, transferring power to the rear wheel through a 5-speed gearbox and belt final drive. Internal engine geometry specifies a bore and stroke of 95.3 x 101.6 mm (3.8 x 4.0 inches) with a 8.9:1 compression ratio.
On the scales, the FLHRSI Road King Custom measures 341.1 kg (752 lbs) wet (curb). Rider ergonomics and chassis geometry center around a 663 mm (26.1 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 18.92-liter (5 US gal) fuel tank paired with a rated consumption of 5.34 L/100 km provides an estimated theoretical range of roughly 354 km (220 miles) between fill-ups, while factory top speed is listed at 292 km/h (181 mph).
Within MotoLibrary's Harley-Davidson archive, this model family spans 3 indexed model years from 2004 to 2006, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.
Theoretical Range
~354 km (220 mi)
Engine
Displacement1442.2 ccm (88.00 cubic inches)
Engine TypeV2, four-stroke
Engine DetailsV2, four-stroke
Torque116.6 Nm (11.9 kgf-m or 86.0 ft.lbs) @ 3500 RPM
Compression8.9:1
Bore x Stroke95.3 x 101.6 mm (3.8 x 4.0 inches)
Fuel SystemInjection. Electronic Sequential Port Fuel Injection (ESPFI)
Fuel ControlDouble Overhead Cams/Twin Cam (DOHC)
CoolingAir
Transmission
Gearbox5-speed
Final DriveBelt (final drive)
ClutchMulti-plate with diaphragm spring in oil bath
Performance
Top Speed292.0 km/h (181.4 mph)
Fuel Consumption5.34 litres/100 km (18.7 km/l or 44.05 mpg)
Greenhouse Gases123.9 CO2 g/km. (CO2 - Carbon dioxide emission)
ExhaustChrome, cross-over duals
Chassis
Rake26.0°
Trail157 mm (6.2 inches)
Wheelbase1613 mm (63.5 inches)
Ground Clearance119 mm (4.7 inches)
Wheels & Brakes
Front TyreMT90-B16
Rear TyreMU85-B16
Front BrakesDouble disc
Front Brake Ø292 mm (11.5 inches)
Rear BrakesSingle disc
Dimensions & Weight
Dry Weight327.0 kg (721.0 pounds)
Weight incl.341.1 kg (752.0 pounds)
Seat Height663 mm (26.1 inches) If adjustable, lowest setting.
Alt. Seat Height688 mm (27.1 inches) If adjustable, highest setting.
Overall Length2380 mm (93.7 inches)
Fuel Capacity18.92 litres (5.00 US gallons)
Other
Color OptionsVivid black, black cherry, black pearl, deep cobalt, glacier white pearl, rich sunglo blue, yellow pearl, brandy wine sunglo
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.
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.
