https://advrider.com/harley-davidson-revolution-max-1250-engine-the-mocos-future/The Revolution Max 1250 engine (a 60-degree V-twin) takes things much further. Along with liquid cooling, the engine also has a computer-controlled variable valve timing system (VVT) on both the intake and exhaust camshafts. Other manufacturers (BMW, Ducati) have variable valve timing, but only on the most expensive, advanced bikes, so Harley-Davidson is exploring new territory here.
According to H-D’s presser, the VVT system “advances or retards exhaust and intake camshaft timing independently through a potential range of 40 degrees of crankshaft rotation.” You know how motojournos always say an engine is “tuned for torque” or “tuned for horsepower”? Well, this allows Harley-Davidson to tune for both. The presser says “VVT broadens the overall powerband and improves torque management and efficiency compared to the same engine with fixed valve timing. This allows the same engine to provide both low-end grunt for acceleration off the line as well as the thrill of high-RPM horsepower.” Harley-Davidson also says it can improve fuel mileage.
The engine itself uses single-piece aluminum cylinders, forged aluminum pistons, and magnesium rocker covers, cam covers and primary cover. Not exactly mind-blowing technology, but you need to make these steps to improve performance or reduce weight, or both. The heads are aluminum as well; because the heads are a key mounting section of the chassis, Harley-Davidson used targeted heat treating to make them flexible at the mounting point, but rigid over the combustion chamber.
