Softail Street Bob Dark Custom

2018 Harley-Davidson Softail Street Bob Dark Custom Technical Analysis & Specification Breakdown

Engineered by Harley-Davidson for the custom - cruiser motorcycle segment, the 2018 Harley-Davidson Softail Street Bob Dark Custom relies on a 1690 cc (103.1 cu in) air-cooled v2, four-stroke powerplant. In factory specification, peak output is rated at 86 HP (62.8 kW) at 5,020 rpm while maximum torque reaches 127 Nm (93.7 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 50.9 HP per liter and a 1,770 rpm working window between peak torque (3,250 rpm) and peak power (5,020 rpm), the engine character is prioritizing low-RPM tractability, mechanical longevity and relaxed throttle response over peak redline numbers.

On the scales, the Softail Street Bob Dark Custom measures 304 kg (670 lbs) wet (curb), translating to a power-to-weight ratio of 0.28 HP/kg (3.53 kg per horsepower). Rider ergonomics and chassis geometry center around a 680 mm (26.8 in) seat height — giving shorter riders and urban commuters confident flat-foot reach at traffic stops, combined with a 1,630 mm (64.2 in) wheelbase engineered for planted straight-line stability. The 13.2-liter (3.5 US gal) fuel tank paired with a rated consumption of 5.6 L/100 km provides an estimated theoretical range of roughly 236 km (147 miles) between fill-ups.