We’ve sourced spy shots of two test bikes at the Vallelunga circuit near Rome. At least one appears to be in near-production form, with a licence plate bracket, full lighting, mirrors and even a legally-required rear reflector in place. The market for traditional, 600cc-class sportsbikes has been in a downward spiral for years, but a lusty, middleweight twin-cylinder engine could refocus this segment. The RS660 is based around a parallel-twin engine that’s effectively the front two cylinders from Aprilia’s 1078cc V4 superbike and it should be good for at least 75kW (100hp). It’s likely to weigh around 160kg, giving it an impressive power-to-weight ratio.
By Ben Purvis
