Technology is a many splendored thing. Just look at the ways in which technology has shaped our lives: written letters have given way to emails, cell phones have (almost) made landlines a thing of the past, and who needs a map when you've got a GPS? In many ways, technology has made once arduous tasks more convenient.
Yet the internal combustion engine and the method by which it delivers its power to the road has remained largely the same for the past century. A power transfer device of some sort distributes the power from the crankshaft to a set of constant mesh gears which then distributes that forward motion to the driven wheel or wheels (over simplified of course). It's been the same for ages. And as the saying goes; if it ain't broke, don't fix it. Right?
Wrong. At least according to Aprilia. There are some drawbacks to the conventional method of forward motion transfer, and borrowing a rather new technology from the four-wheeled spectrum, Aprilia has equipped its new Mana 850 with a CVT, or Continuously Variable Transmission. We'll get more in-depth with the CVT later, but let's switch gears (pun intended) and talk about the rest that the Mana has to offer.
Sum Of Its Parts
The Mana isn't exactly a sportbike, but it is an awfully nice tool to tackle the everyday needs of a rider. To start, the Mana's steel trellis frame cradles the 850cc 90-degree V-twin. Like its Shiver stablemate, this engine is also manufactured entirely in-house. On the dyno, the Mana put out a disappointing 55 horsepower and 40 lb-ft. of torque. That torque curve, however, is flat as a board throughout the entire rev range, providing decent acceleration no matter what rpm you're in. Of course, you'll never know how fast the engine is spinning because there is no tachometer on the sparse gauge cluster. The speedometer dominates the gauges, while an LCD screen displays drive mode selection and gear position, assuming you're shifting gears manually. In their infinite wisdom, the folks at Aprilia must have figured that since it can shift itself there's no need for you to know the engine speed. Word to Aprilia: we want the tach back.
Suspension duties are provided by a non-adjustable 43mm inverted fork with 120mm of travel, while an offset shock is mounted directly to the swingarm without the use of linkages. Adjustability is limited to preload and rebound damping. Stopping power in the front is by way of four-piston, radially mounted calipers hugging 320mm disks. Oddly, stopping power by these binders is sub-par from what we've come to expect from Aprilia. The bike will respond to an input at the lever, but that eye-popping bite isn't there. Not to say that the brakes are weak, but the Mana takes a little more effort than we're used to giving for an Aprilia.
The Mana features a wide, flat handlebar that gives it great leverage in the tight stuff and low set footpegs which provide a neutral riding position. Despite the low pegs, the sidestand makes contact with the pavement before your feet. Oddities include a gas tank whose filler tube is located under the passenger seat. Aprilia engineers then placed the tank closer and lower to the C of G for improved handling. We noticed a difference in the responsiveness of the chassis with a full tank and one bordering on empty. The full tank clearly required more effort to turn and wasn't as agile. So what's the deal with the "conventional" gas tank? Well that's now a storage unit. One equipped with a soft, non-scratch lining. There's a small compartment for the toolkit and a cell phone and even a 12 volt A/C outlet to power a phone charger. A full face helmet is claimed to be able to fit, but none of ours did. Nonetheless, this is one of the conveniences of the Mana: a built-in tankbag at no extra charge.
What's This CVT Thingamajig?
Right, the CVT. Like we mentioned earlier, the basic premise behind traditional gearboxes is that power is spread through constant mesh gears with a fixed amount of teeth. The "problem" with this setup is two-fold: first, there are times when the vehicle is hunting between gears (say on an incline) and the ratios between two gears will either cause the engine to spin incredibly high, or so low that it can't put down enough torque to maintain speed. The second issue is the sudden (and albeit very minute) loss of momentum as the gears are changed from one to another.
A continuously variable transmission eliminates those issues by always operating at optimum rpm for a given speed. Simply put, a CVT has three main components: a V-shaped, high strength metal or rubber belt, a cone-shaped driving pulley of varying diameter that's connected to the engine's crankshaft (like a countershaft sprocket), and a cone-shaped driven pulley, also of a varying diameter, that drives the rear wheel (like a final drive sprocket). At slow speeds the driving pulley is large, while the driven pulley is small, to enable the vehicle to accelerate quickly. As speed increases, the two pulley's diameters will start to inverse, effectively creating an infinite amount of gear "ratios." That isn't to say that you'll continue to accelerate forever, as aerodynamics, as well as the physical size of the pulleys, will ultimately determine top speed.
There are other factors at play here, such as electronic aids that play a part in the system. As for the Mana, its seven gears are set at pre-determined ratios which are ultimately decided upon automatically (when in Autodrive) or electronically when in sequential shift mode.