VFR1200F DCT Test
Technology - motorcyclists thrive on it. Whether you enjoy crossing the interstate, dragging a knee, clearing a triple, gapping two boulders, or simply commuting to work, technology is what makes our motorcycles more enjoyable.
VFR1200F DCT Test
Technology - motorcyclists thrive on it. Whether you enjoy crossing the interstate, dragging a knee, clearing a triple, gapping two boulders, or simply commuting to work, technology is what makes our motorcycles more enjoyable. Since 1885, when Gottlieb Daimler installed Nicolaus Otto's four-stroke internal-combustion engine into a wooden bicycle frame, the motorcycle has enjoyed a continued transformation brought about by technological advancement.
When Honda entered the 1959 Isle of Man TT race with five motorcycles, it started a long quest for excellence through advancing technology that eventually made it to the showroom floor. Half-a-century later Honda introduces a technological wonderland, the 2010 Honda VFR1200F.
When I first heard about the new VFR1200F, it was introduced to me as "the bike with the dual-clutch transmission." As a longtime fan of endurance auto racing and World Rally Championship, I was already familiar with the dual-clutch transmission (DCT) concept and was excited to see this technology applied to a production motorcycle.
What I didn't know at the time was the DCT is only the most overt of the technological advancements in the VFR1200F. There is some intriguing technology in this bike that makes it a true innovation, and hopefully the foundation of more two-wheeled magic to come.
I had anticipated the experience of riding the VFR1200F with DCT to be a strange one. After all, I've been riding for 32 years with nothing but the tried-and-true manual transmission. To my surprise using the DCT is very intuitive and easy to get used to. I suspect this is because most cars have automatic transmissions and the DCT has a similar feel, even considering it is on a motorcycle.
After the first two stoplights, I no longer thought about grabbing the clutch. I simply applied the brakes and came to a stop; the motorcycle clicked down through the gears for me and disengaged both clutches. Accelerating is equally simple -- twist the throttle and watch the gear indicator climb. One note: if you have the habit of blipping the throttle while waiting at a light, you have to cut that out, or you will quickly find yourself lurching into the intersection.
The DCT concept was invented shortly before World War II by Adolphe Kégresse, a French military engineer who also invented the half-track truck, but it was not developed until Porsche introduced the Doppelkupplungsgetriebe in the 1980s for its Porsche 956 and 962 Le Mans racecars. Audi also used a DCT in its Sport Quattro S1 rally car around the same time. DCT was not seen off the racetrack until the 2003 Volkswagen Golf Mk4 R32 was introduced. Now it is appearing in an increasing number of high-end automobiles.
As the name indicates, a DCT has two clutches -- one clutch operates the odd numbered gears and the second clutch operates even numbered gears. In the VFR1200F, both clutches are in line on the same shaft and share a common clutch basket. This layout keeps the size of the clutch equivalent to that of a traditional motorcycle clutch. The main shaft is comprised of an inner shaft that fits inside an outer shaft allowing power transfer from each clutch to its respective gear cluster. Aside from two clutches and a concentric main shaft, the DCT is the same as any other one-down, five-up constant mesh transmissions.
Engine oil is used as hydraulic fluid to open and close the pressure plates in the clutch. Oil is drawn from the crankcase, filtered, and regulated using two linear solenoid valves that act as the master cylinder for each clutch. Oil is plumed through the center of the main shaft into piston chambers in the center of the pressure plate assemblies.
The advantage to a dual clutch system is it gives you very fast shift times. In a manual system, the clutch is disengaged, the next gear is selected, and the clutch is engaged. In a DCT, the time it takes to select the next gear is eliminated from the process. Changing gears is computer controlled, so the ECU tries to anticipate what the next gear should be and it pre-selects it. This gear can be pre-selected because it is driven through the second clutch, which is disengaged.
Once the engine reaches the appropriate RPM, the computer disengages the first clutch and engages the second clutch, which applies power through the next gear. All the time used to change gears is taken by switching from one clutch to the other.
Taking off from a stop is also computer-controlled. There is no clutch lever, so all you do is twist the throttle and, as the rpm increases, the first clutch smoothly engages to propel you forward.
The bike starts in neutral when the engine is fired and the drive mode must be selected before riding. Three drive modes are available: "Drive" mode provides a conservative shift program that is appropriate for most riding and gives the best fuel economy; "Sport" mode provides an aggressive shift program where shifts occur at higher engine speeds; "Manual" mode allows the rider to select gears using the shift buttons on the left grip. Each mode can be selected on the fly, so the bike can change to match the rider's mood and road conditions.
Taking the VFR1200F to the twisties is a wondrous experience. With a light and responsive feel, it is easy to throw this machine into the corners, grab a ton of braking, and accelerate out. The linked ABS allows you to decelerate hard and the automatic transmission ensures you have plenty of gear when exiting the turn. "Sport" drive mode is more than sufficient for this type of riding, but if you still want to use engine breaking when decelerating, put it in "Manual" mode and let your left thumb dance across the downshift button.
On the highway, the relaxed ergonomics of the VFR1200F (compared to a pure sport bike) combined with the DCT makes for a competent sport-touring package. Taking advantage of the VFR1200F's versatility, Honda designed an integrated luggage system into the bike. Optional 29-liter hard side bags easily lock into slots in the sub-frame and behind the passenger pegs.
No ugly pannier frame to install, just clean lines with the side bags on or off. The 33-liter trunk glides on an energy absorbing rack that mitigates the top-heavy feeling when riding aggressively with a full tail bag. Other touring options include bag liners, windscreen deflector, fairing deflectors, asymmetrical heated grips, low seat, center stand, hugger, 12-volt socket, and the ever-popular tank bag.
The styling on the VFR1200F is pure manga brought to life. The front view of the headlight cowling is reminiscent of a menacing robot's faceplate; cheeks protected by side covers that direct airflow into the engine compartment. Hidden fasteners are used to keep the visual flow unhindered and align all plastic panels for an incredibly precise fit.
The bodywork is angular yet no sharp edges are present to disturb the smooth flow around the machine. Seated in a comfortable upright position, the short windscreen directs windblast to about eye level and over the shoulder. An opening at its base of the screen induces a laminar flow of air along the inside edge of the windscreen to cut down on turbulence.
Shrouded by the body panels is the true menacing aspect of the VFR1200F. Honda has a long history of producing prodigious V-4 engines and putting them in highly capable motorcycles. For 2010, Honda has incorporated technology from its RC212V MotoGP engine into an advanced 1237cc V-4 with some interesting features. Historically, VFR engines have used a 90-degree cylinder.
Bringing the concept of mass centralization from the racetrack to the street, Honda decreased the cylinder angle to 76-degrees, making the engine more compact front to back. The forward cylinders are spread wider apart than the rear cylinders making the engine very slim at the rider compartment, allowing for a narrower frame thus giving the sensation that you are embedded in the motorcycle as opposed to sitting on top of it.
In conjunction with the decreased cylinder angle, the crankshaft has a slight offset between the crankpins that connect the front pistons and the crankpins for the rear pistons. Honda titled this Symmetrically Coupled Phase-shift Crankshaft. The 28-degree offset between the front and rear crankpins negate primary engine vibration allowing the engineers to omit a counter balance shaft, which saves about three pounds of rotating weight. Any reduction in rotating mass makes a bike feel lighter when changing direction. What vibration persists only adds to the high-performance sensation that emanates from the VFR1200F.
Another reduction in engine size and rotating mass is accomplished by incorporating the exclusive Unicam valvetrain into the cylinder heads. Honda's unique system uses a unique one-cam-per-cylinder-head with the intake valves directly actuated by the cam and the exhaust valves actuated by roller rockers, a technology brought over from the CRF-R motocross machines. This gives a 10,200 rpm redline while allowing for a flat combustion chamber providing a quick, efficient burn.
Technical innovation does not stop at the top of the engine. Straight from MotoGP, the sealed crankcase has reduced air pressure inside, which decreases wind resistance under the reciprocating parts. This is accomplished by using a scavenging pump that pulls oil and gasses out of the crank chamber. Oil pressure is constantly monitored to ensure the engine is operating within appropriate parameters.
Airflow through the engine starts with each cylinder getting a 44mm throttle body with 12-hole injector, all controlled by Honda's first Throttle By Wire (TBW) system, there is no mechanical connection between the throttle grip and the injector unit. The throttle is connected to the position sensor under the tank by traditional cables. This helps maintain the expected feeling when twisting the throttle in addition to moving the position sensor lower in the frame.
Throttle position is monitored by an ECU which incorporates data from the engine crank speed, manifold pressure, selected gear, coolant and intake air temperatures, and vehicle speed to calculate the precise settings required for the motorcycle to perform at its best at that moment. Your hand twists the throttle, which tells the computer what you want. The computer then adjusts the fuel injection to give a more accurate response than a conventional mechanical control.
Once the air/fuel mixture is burned, it passes out through the asymmetrical exhaust system. The length of the front pipes is different from the rear pipes. Honda did this to tune the power delivery of the engine by altering the exhaust pulse. It also gives the VFR1200F an exotic sound, something akin to an inline triple. The trapezoidal muffler has a bypass valve that opens when the engine reaches 6000 rpm.
This gives excellent low rpm torque, about 90 percent peak torque at 4000 rpm, yet allows the engine to breath freely at speed. The sensation when the bypass valve opens is extraordinary. Off the line, you get a satisfying linear pull then once the engine hits 6000 rpm the bike leaps forward with a burst of horsepower. This type of dual-personality gives the VFR1200F a versatility anyone can appreciate.
To package up the VFR1200F engine nicely, a rigid yet light four-piece twin spar aluminum frame is used to attach all the necessary rolling gear. Leading off the hardware is the 43mm inverted cartridge fork giving 4.7 inches of travel with adjustable spring preload. The Pro-Arm single-sided swing arm provides 5.1 inches of travel using a single Pro-Link gas-charged shock with remote preload adjuster and adjustable rebound.
As with the other open class sport bikes, the VFR1200F uses shaft driv. But, unlike the others, Honda engineered the swingarm with a pivot point that is offset from the output shaft. The drive shaft telescopes to compensate for length changes in the driveline as the swingarm travels in its arc. Having the driveshaft under the swingarm pivot point accomplishes several things.
The engine can be made more compact when the output shaft is placed under the transmission countershaft. The swingarm pivot can be wider because it does not have to accommodate the drive shaft pivot. This allows for a wider mounting position in the frame making the swingarm more rigid. With a higher mounting point, the swingarm can be longer without increasing the motorcycle's wheelbase, which improves handling and traction.
Stopping is accomplished with as much technical aplomb as Honda put into the rest of the VFR1200F. The front wheel is slowed with dual 320mm floating disks squeezed by six-piston calipers, and a single 276mm disk with a two-piston caliper on the rear. Front and rear calipers are linked using Honda's Combined Braking System. When the brake lever is pulled, three pistons on the front right disk and two pistons on the front left disk are sent to work.
To ensure equal force is applied to both disks, the left two pistons are two and five millimeters larger in diameter than the right pistons. When the foot brake is applied, the two pistons on the rear disk and two pistons on the front left disk are applied. A delay valve is used on the front to even out the breaking force between the front and back wheels. All of this is routed through an ABS modulator.
Honda developed the new VFR1200F to showcase its new Dual Clutch Transmission. Fortunately, the engineers did not stop there, because this bike is more than just a motorcycle with a cool new transmission. The VFR1200F is a pure expression of technological advancement that keeps motorcycling fresh and exciting.
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