After being teased over the past couple of years, the 2021 April RS660 has finally been unveiled, with its first public showing in California, US. The RS660 is Aprilia’s return into the modern middleweight sports bike market, after the issue of the Shiver 750, Dorsoduro 750 and Mana 850GT a decade ago, while Malaysian riders might recall the Pegaso 650 adventure-tourer from the 90s.

As a pure sports bike, complete with full-fairing, the RS660 can perhaps best be seen as the 2020 equivalent to the RS250 two-stroke, which in both street and race form, launched many a racing career. In this case, an all-new 660 cc, parallel-twin in the RS660’s chassis produces 100 hp at 10,000 rpm and 67 Nm of torque at 8,500 rpm.

Euro 5 compliant, the two-cylinder mill is derived from the front bank of Aprilia’s 1,100 V-four as installed in the Aprilia RSV4. With the cylinders leaned towards the front wheel, the centre of gravity for the RS660 is moved forward, placing weight on the front wheel and improving weight distribution.

The engine’s firing order is offset by 270-degrees, making the RS660 behave more like a V-twin, much like Yamaha’s MT-07 parallel-twin. 80% of the RS660’s engine torque is available at 4,000 rpm, with 90% torque at the rider’s request when engine speed reaches 6,250 rpm.

Twin 48 mm throttle bodies connected to variable length intake tracts provide optimised power delivery for the RS660 at high and medium revs. For comparison, the Yamaha MT-07, the RS660’s closest equivalent in terms of displacement and engine configuration, produces 74.8 PS at 9,000 rpm and 68.0 Nm of torque at 6,500 rpm from 689 cc.

For riding aids, the RS660 comes fully-equipped with five riding modes – three for the street and two for track use – while multi-map corner ABS is standard. Additionally, there is software management for traction and wheelie control, along with cruise control, quick shifter and engine brake and mapping.

There are three colour options for the 2021 Aprilia RS660 – Acid Gold, Lava Red and Apex Black. For racing purposes, a full range of factory options is available, including Akrapovic full-system exhaust with mapping and software enabled race shift pattern which gives “one-up, five-down” shifting with no component replacement.