TUAREG TWIN

TECH TALK

To create Aprilia’s first-ever parallel-twin engine design powering the Tuareg 660 and its Tuono/RS660 sisters, its first middleweight four-stroke motor since the SXV450/500 V-twins developed strictly for off-road use 20 years ago, the Italian marque’s R&D engineers essentially sliced their seven-time World Superbike champion (three Riders crowns, four Manufacturers titles) RSV4’s unique 65° V4 motor in half, took the front bank of cylinders and stroked the result to produce a liquid-cooled eight-valve 659cc power unit measuring 81 x 63.93 mm. This very compact lightweight wet-sump design, with a 270° crankshaft and single gear-driven balance shaft to reduce any remaining vibration, weighs just 57kg dry including the two 48mm ride-by-wire Marelli throttle bodies, each with a single injector. The forged pistons whose wrist pins feature a DLC coating for improved durability, sit on split steel conrods mounted on the one-piece plain bearing 180-degree crankshaft (so, one-up, one-down, piston-wise) T