All we have ever wanted are motorcycles with mass horsepower and racing-derived technical excellence. These wishes have driven manufacturers down the roads of potent open-class literbikes, homologation-special superbikes, and race-replica machines—nowadays often with 190-plus claimed horsepower. But maybe we’ve asked for too much?

In this episode of <i>MC Track</i>, we rip laps aboard the 2021 Aprilia RS 660 at the Ridge Motorsports Park in the Pacific Northwest. (Jeff Allen/)

Sure, rubber-burning horsepower and unlimited funds make for wicked sportbikes, but it isn’t everything when it comes to having a seriously good time, and the 2021 Aprilia RS 660 is a prime example. It’s a motorcycle that represents a balance of performance and practicality. Engaging engine performance, nimble handling, a relatively low seat height, and roomy ergonomics make the 660 as much of a ripping sportbike as it is an everyday machine. And although it isn’t built for cutthroat competition, it has enjoyed success in the MotoAmerica Twins Cup championship, taking several victories to date.

As part of an Aprilia Racers Days event at Ridge Motorsports Park in the Pacific Northwest, we had the opportunity to sample the RS 660 on the racetrack for the first time. The circuit’s 2.5-mile, 16-turn layout of fast sweepers, hard braking zones, wide-open straightaways, and dramatic elevation changes meant no aspect of the RS went untested.

The RS 660 is powered by the same 659cc parallel-twin engine also utilized in Aprilia’s Tuono 660 and Touareg 660. Placed on the <i>Motorcyclist</i> dyno, it ripped out nearly 90 horsepower and 45 pound-feet of torque at the rear wheel. (Jeff Allen/)

Opening the throttle of the RS 660 unleashes immediate, usable power from its RSV4-derived 659cc parallel-twin engine, pulling strongly with very linear initial acceleration before truly ripping around the 8,000-rpm mark. Here, the RS barks out a meaty growl as it rips toward redline that is eerily similar to its V-4 sibling. Still, it doesn’t have mass superbike horsepower to fall back on, and keeping momentum means perfecting midcorner speed.

Brembo monoblock calipers are employed to provide the RS 660 stopping power. Combined with the adjustable engine brake management system, deceleration is quick and confidence inspiring. (Jeff Allen/)

And that’s what distinguishes the RS 660. Peak performance isn’t as impressive as the 600cc inline-four repli-racers, but an impressively flat torque curve and usable, low-end delivery means taking advantage of the power available isn’t as arduous—keeping the engine spinning above 12,000 rpm isn’t required. It’s also less intimidating than open-class superbikes, while still offering an engaging experience for experts and serving as a conducive platform for improving riding skill. For reference, the 660 produced 88.8 hp at 10,500 rpm and 45.3 pound-feet of torque at 8,500 rpm on the Motorcyclist dyno.

Although not designed for competition, the RS 660 is dripping in race-inspired details. The side cowlings feature integrated aerodynamic winglets, similar to those seen in the RSV4. (Jeff Allen/)

To keep things in check, the RS 660 is equipped with the Aprilia Performance Ride Control (APRC) electronic rider-aid suite, which is accessed via a full-color TFT display. These IMU-based traction control, wheelie control, engine-brake, and ABS settings are offered in five preset riding modes, with Challenge and Time Attack settings being designated track modes. The latter modes include features like a built-in lap-timer function. Utilizing level 2 of traction control and wheelie control off, the RS 660 blends tractable power delivery and logical electronic intervention for aggressive-yet-manageable acceleration at corner exit without being robbed of its sporty personality. In simple terms, it’s superbike-level precision in a middleweight package.

The narrow ergonomics package showcases a slim 4.0 gallon fuel tank. Topped off, the RS 660 weighs 401 pounds. (Jeff Allen/)

Measured at 401 pounds fully fueled on the Motorcyclist scales, the maneuverability of the RS 660 is impressive. Required steering effort is minimal as it carves with an any-apex-anytime attitude. Strong connection and excellent grip via the OE-fitted Pirelli Diablo Rosso Corsa II tires boosts confidence to test the trail-braking limits, while providing superb drive grip. Semi-aggressive ergonomics that we came to love on the street are appreciated on the racetrack too. While not as cramped as traditional supersports, the riding position is still compact enough to hustle the 660 around the racetrack, but will probably conserve energy for more laps—and maybe even the ride home. Yes!

The Aprilia RS 660 is an all-around machine with an emphasis on sporting capability. Whether you’re a racer or not, it makes you feel as if you’re competing in the next middleweight GP. (Jeff Allen/)

The RS 660 is superb at corner entry too. A firm squeeze to the lever of the Brembo Monoblock calipers will bring the Aprilia to a quick halt and with good feel. Add in the APRC’s three-level engine-brake control, which adds adjustability to the deceleration characteristic and boosts confidence at the front tire’s contact patch. Suspension action adds confidence as well. The 41mm KYB fork and shock are spring preload and rebound adjustable, but provide a strong balance of big-input support and small-bump compliance in box-stock trim. That said, compression damping would be welcomed in dialing in settings to personal liking.

While the $11,499 as tested MSRP of the 2021 Aprilia RS 660 may ride the higher end of the parallel twin market, it represents the premium touch and quality engineering expected of the Noale-based manufacturer. (Jeff Allen/)

It’s hard to argue the balance of power and performance that Aprilia has created in the RS 660. While not as ruthless as a full-size RSV4 superbike, the 660 offers an addicting power delivery that can entertain seasoned veterans and track beginners alike while its corner-carving precision, nimble handling, and precise electronic intervention can be appreciated by all.

Gear Box

Helmet: Shoei RF-SR

Suit: Alpinestars Tech-Air Custom

Gloves: Alpinestars GP Plus R

Boots: Alpinestars Supertech R

2021 Aprilia RS 660 Specs

Source: MotorCyclistOnline.com