The Harley-Davidson Revolution Max 1250 Engine
On February 22, 2021, Harley-Davidson® officially unveiled the multi-year teased then full-frontal hyped all-new Liquid-Cooled V-Twin (Revolution® Max 1250 Engine), which powers the new Adventure (ADV) segment (Touring and Sport) motorcycle called the Pan America™ 1250. The Revolution Max 1250 engine is assembled at the Harley-Davidson Pilgrim Road Powertrain Operations facility in Wisconsin.
The new engine is tuned specifically to deliver the desirable power characteristics for the Pan America 1250, with an emphasis on smooth low-end torque delivery and low-speed throttle control applicable to ADV off-road riding.
Harley-Davidson is bent on piloting across a dusty path into the deep-sand of the Dakar trail by taking on the most iconic and recognizable adventure motorcycle — the BMW GS. The GS, a direct descendant of a Dakar winner, has spent decades proving its capability in the remote parts of the world, with each generation improving on the last.
Revolution® Max 1250 Engine Summary:
•Displacement: 76.3 cu in (1,252 cc)
•Bore x Stroke: 4.13 in (105 mm) x 2.83 in (72 mm)
•Maximum horsepower: 150 @ 9000 rpm
•Maximum torque: 94 ft/lbs @ 6750 rpm
•Peak RPM: 9500
•Compression Ratio: 13.0:1 (Piston crowns are machined)
•Valvetrain: Chain-driven, DOHC, hydraulic self-adjusting lifters, intake & exhaust VVT; four valves per cylinder
•Primary Drive: Gear
•Final Drive: Belt
More Revolution® Max 1250 Engine Details:
•60-degree V angle of the cylinders.
•Single-piece aluminum cylinders with nickel silicon carbide-surface galvanic coating.
•Rocker covers, camshaft covers and primary cover are lightweight magnesium.
•Liquid cooled engine and the engine oil is also liquid cooled. Oil cooling jets are aimed at the bottom of the pistons.
•The two crankshaft connecting rod journals are offset by 30 degrees which creates a 90-degree firing order.
•The engine requires premium-grade (91 octane) fuel.
•Four-valve cylinder heads (two intake and two exhaust) — exhaust valves are sodium-filled.
•Cylinder heads are cast from high-strength 354 aluminum alloy.
•The engine has Double Overhead Camshafts (DOHC) with Variable Valve Timing (VVT).
•The engine features roller-finger valve actuation with hydraulic lash adjusters and has multiple internal balancers.
•The engine has two spark plugs per cylinder, dual down-draft throttle bodies with an 11-liter air box over the engine and washable conical air filter.
•The is a unitized powertrain, i.e. the engine and transmission are housed in a common case.
•There is a six-speed transmission and the clutch is mechanically actuated with a large-diameter cable.
Harley-Davidson stated that the Pan America adventure motorcycle powered by the Revolution Max 1250 engine can achieve a top speed of 135 mph (217 kmh)!
Similar to the crossover in the four-wheeled world, the adventure motorcycle segment has now been expanded, thanks to Harley-Davidson.
Images courtesy of Harley-Davidson.