2023 Aprilia RS 660 in Racing Black. (Aprilia/)

Ups

• Friendlier ergos than race-replica sportbikes
• Class-leading electronic rider aids
• Twin-cylinder performance tuned for the street and ready for the track

Downs

• Does anyone else miss V-configured engines?
• Still priced similar to 600cc inline-four sportbikes

Verdict

Aprilia’s RS 660 is a heavy hitter in the middleweight supersport category, delivering serious performance and lauded versatility. It’s more practical than howling inline-four 600s in terms of overall flexibility and comfort but still plenty of fun around a racetrack or on a spirited street ride.

2023 Aprilia RS 660. (Aprilia/)

Overview

The Aprilia RS 660 is a direct response to the market’s shift away from the 600cc middleweight sportbikes that consumers have lately deemed too expensive, too uncomfortable, and too specialized. Aprilia’s response was to build an affordable, more flexible sportbike.

The RS 660 is a lightweight, compact, and easy-to-ride sportbike powered by a liquid-cooled parallel-twin engine of 81.0 x 63.9mm bore and stroke that produces a very broad, flat torque curve. The engine is carried in a bolted-together cast aluminum chassis in a MotoGP-style fairing. To defray development costs, the parallel-twin engine powers multiple models (the Tuono 660 and the Tuareg 660, both of which have proven real hits).

Top-shelf electronics underline the RS 660′s provenance, and despite an affordable price tag and comparatively neutral riding position—attributes sportbike purists tend to associate with watered-down performance and compromise—the riding experience is anything but middle of the road. In essence, the RS 660 represents a new way forward for middleweight sportbikes.

2023 Aprilia RS 660. (Aprilia/)

Updates for 2023

The Aprilia RS 660 is virtually unchanged for 2023, aside from new liveries. The up-spec Extrema is new for 2023.

Pricing and Variants

The RS 660 is available in three colorways for 2023: Racing Black, Tribute, and Acid Gold. The Racing Black and Tribute models retail for $11,499 while Acid Gold retails for $200 more.

The Extrema model is designed to be as light as possible. It is equipped with an SC-Projects exhaust, plus carbon fiber bellypan and front mudguard. It has a single-seat tail unit and is prewired to run standard or GP shift. MSRP is $13,499.

Competition

In terms of intent, the RS 660′s closest competitor is the Yamaha YZF-R7 ($9,199). The RS 660 is significantly more expensive, but includes a full suite of electronic rider aids and higher-spec components. Honda’s CBR650R ($9,899) is another full-fairing sportbike that walks the line between comfort and performance, but was designed with little intention of hitting the track.

2023 Aprilia RS 660 in Aprilia’s Tribute colorway. (Aprilia/)

Powertrain: Engine, Transmission, and Performance

On the CW dyno, the RS 660′s 659cc parallel twin produced 89.16 hp at 10,520 rpm and 44.85 lb.-ft. of torque at 9,540 rpm. Despite the overall flexibility in power delivery, thanks to a relatively flat torque curve with nearly 80 percent of torque available at 4,000 rpm, the RS 660 is happy at high revs. A slight bump in horsepower is seen at 7,000 rpm, which allows the RS to rip toward redline. This is where the fun is had.

Kevin Cameron notes: “Aprilia has something of great value in the refined combustion chambers and ports of its RSV4 superbike, so it made sense to share them with RS 660, giving it good horsepower at a moderate 10,500 rpm. This is strong performance from a 40.2ci parallel twin, especially with a high and very wide 21st century torque curve that gives outstanding drivability (the rev limiter steps in at 11,500). This is torque so flat that it’s hard to find a peak, for the quoted maximum of 49.4 lb.-ft. varies only a percent or so between 8,500 and 10,500. Ninety percent of that is available from 6,250 and 80 percent from 4,000. That is a torque plateau, not a curve. Flat is good.

“To counter secondary shaking force (which arises from the twice-per-revolution changes in connecting-rod angle),” Cameron continues, “the two crankpins are set at 270 degrees. By opposing rather than adding those secondary forces, this cancels them. The result is humane smoothness for all-day riding. That 270-degree crankpin spacing also replaces the traditional drone of an even-firing parallel twin with the more muscular syncopated sound of a V-twin.”

That adds up to a versatile engine that’s appropriate for day-to-day and trackday riding.

2023 Aprilia RS 660. (Aprilia/)

Chassis/Handling

The RS 660 has an aluminum chassis made in two pieces—right and left—assembled by bolts. This frame ends and attaches at the top of the gearbox—the swingarm pivots on the engine itself. Wheelbase is a quick-turning and short 53.9 inches, while the steering rake and trail are 24.1 degrees and 104.6mm (4.1 inches).

The RS 660 is praised for its light handling. It quickly negotiates side-to-side ess turns with ease, while remaining very neutral with excellent weight distribution. A strong connection to the front tire’s contact patch bolsters confidence at any speed, resulting in pinpoint precision through corners.

Brakes

A pair of four-piston Brembo calipers clamping 320mm discs up front quickly bring the relatively lightweight (a CW measured 401 pounds) RS 660 to a halt. A single two-piston Brembo caliper and 220mm disc handle rear braking.

Fuel Economy and Real-World MPG

Claimed fuel consumption is 47.8 mpg.

Ergonomics: Comfort and Utility

In a ride aboard the 660, test rider Bruno dePrato praised the ergonomics saying, “The rider triangle is laid out well, so getting perfectly settled and in control of the Aprilia RS 660 is instinctive and user-friendly.” Its claimed 32.3-inch seat height provides an easy reach to the ground even for riders of below-average height.

2023 Aprilia RS 660. (Aprilia/)

Electronics

Aprilia’s suite of race-inspired electronics is managed by a six-axis IMU and includes five ride modes, an up/down quickshifter, a range of engine maps, cornering ABS, traction control, wheelie control, engine-braking control, and cruise control. Cornering lights, automatic high beams, and self-canceling turn indicators are additional features of the LED lighting package. Information is displayed on a TFT dash.

Warranty and Maintenance Coverage

Like all Aprilia models, the RS 660 comes with a two-year unlimited-mileage warranty.

Quality

Aprilia’s premium quality, sophisticated electronics, high performance, and easy-to-ride manner set the RS 660 above the competition, arguably putting it in a realm of its own.

2023 Aprilia RS 660 Claimed Specs

MSRP:	$11,499–$11,699; $13,499 (Extrema)
Engine:	659cc, DOHC, liquid-cooled parallel twin; 4 valves/cyl.
Bore x Stroke:	81.0 x 63.9mm
Transmission/Final Drive:	6-speed/chain
Cycle World Measured Horsepower:	89.16 hp @ 10,520 rpm
Cycle World Measured Torque:	44.85 lb.ft. @ 9,540 rpm
Fuel Delivery:	Fuel injection w/ two 48mm throttle bodies
Clutch:	Wet, multiple disc
Engine Management/Ignition:	Ride-by-wire/TCI
Frame:	Double beam aluminum
Front Suspension:	Kayaba 41mm inverted fork, rebound and preload adjustable; 4.7 in. travel
Rear Suspension:	Monoshock, rebound and preload adjustable; 5.1 in. travel
Front Brake:	Brembo radial-mount 4-piston calipers, dual 320mm discs w/ cornering ABS
Rear Brake:	Brembo 2-piston caliper, 220mm disc w/ cornering ABS
Wheels, Front/Rear:	Aluminum alloy; 17 x 3.5 in. / 17 x 5.5 in.
Tires, Front/Rear:	120/70ZR-17 / 180/55ZR-17
Rake/Trail:	24.1°/4.1 in.
Wheelbase:	53.9 in.
Seat Height:	32.3 in.
Fuel Capacity:	4.0 gal.
Cycle World Measured Wet Weight:	401 lb.
Contact:	aprilia.com

Source: MotorCyclistOnline.com