It is said that several years ago, during a discussion about future models, someone at Aprilia asked what a motorcycle powered by half an RSV4 V-four would look like.
Well, you’re looking at it, and I just spent 200 miles in the hills above Santa Barbara, California.
The new RS 660 is fun, movable, and definitely fast enough to keep you smiling. It has a compact parallel-twin engine that pumps out 100 horsepower and 49 pound-feet of torque (at the crank) through a hot bar adjustment, and it comes wrapped in a dual-mast aluminum frame and is loaded with spec components and all the electronic functions you can think of. In total, the RS is said to weigh a meager 403 pounds with its four-gallon tank full, and it will be in showrooms in December with an MSRP of $ 11,300.
A completely new version of the lightweight twin
Don’t let the RSV4 DNA or the raunchy looks fool you. Contrary to common perceptions, the RS 660 is not another racing motorcycle with lights. It’s designed to hold its own on the occasional track day, to be sure, but first and foremost it’s meant to excel on twisty backroads, highways, and even real-world city streets.
Historically, the 650ish cc class has been economical and mild-mannered, ideal for beginners and pragmatic riders, but not overly exciting or sophisticated. Meanwhile, 600cc supercars have evolved solely for and within the limits of racing, making them too aggressive (in terms of riding position, suspension setup, and engine character) for everyday use.
There has never really been a middle ground, even though many riders (myself included) have climbed onto the SV650 and MT-07 with GSX-R or YZF-R6 and R1 suspension and brakes in an attempt to forge one.
Finally, someone has reinvented the lightweight cufflink category in a way that many of us have always wanted. Aprilia wiped the slate clean and drew a motorcycle with the approachable nature and versatility we all love from lightweight twins, and paired it with slightly more pure performance and high-end components. On top of that, the RS 660 offers a level of technology that even the 600 can’t compete with.
Hit me with the hardware details
Aprilia chose a parallel twin with a 270 degree crank for the sake of size, design freedom and character. There is some truth to the “medium RSV4” thing, although Aprilia didn’t just see a bank of cylinders in the 1100. That would only leave us with 539cc, which would not be competitive. Instead, Aprilia used the same 81.0mm bore as the 1100, but the pistons slide through 63.9mm of stroke for a total displacement of 659cc. The resulting package is compact and offers advantages in terms of weight, engine location, exhaust routing and ergonomics for the driver. The 100 horsepower that Aprilia claims is measured at the crank, which means around 85 ponies are likely to be put on the rear wheel.
The two-cylinder design also offers a wide range of accessible power, with similar behavior to that of a V-twin, thanks to the uneven firing order of the crank design. If you haven’t yet ridden a 270-degree twin, it’s a world apart from the smooth, vibrant feel of the traditional 180-degree arrangement used on a Kawasaki Ninja 300 or 650.
The RSV4 drip extends to the shape of the combustion chambers and ports, which are key aspects of a high-performance engine. Like a high compression ratio, and the 660 goes up to a steep 13.5: 1. Yes, you’ll need to use premium gasoline. Pistons that squeeze things that hard have to withstand a lot of heat, so the jets of oil spray the bottom of the domes and there is an oil / water heat exchanger to keep the lubricant cool. None of this is new technology, but it is rare in this segment.