When building a replacement motor for an icon like the VMax, Yamaha/Star engineers knew they had to recreate a legend. While the old 1198cc V-Four was the bees' knees in 1985, it would take a large injection of power to be king of the hill in 2009.The mantra of the muscle-car era was "there's no replacement for displacement," and the new VMax hums the same tune. While its 66mm stroke was retained, the '09 Max gets a big-bore treatment by enlarging its cylinders from 76mm to 90mm. This yields an engine with 481cc extra, a 40.2% bump to 1679cc.
Like the upcoming Aprilia V-Four Superbike engine, the VMax uses a chain to drive the intake cams, and from there a gear-set turns the exhaust cams, keeping the engine as short as possible. Valve-adjustment intervals are only every 26K miles. Star also tightened up the 70-degree vee cylinder angle to 65 degrees, also the same as the Aprilia mill. Combined, this tightened up the distance between the cylinder heads by a little more than 1 inch, and the monster motor is 7mm shorter overall.
Much of this new engine uses technology seen on Yamaha's top-line sportbikes. A Mikuni fuel-injection system uses a quartet of 48mm throttle bodies with 12-hole injectors, and it's operated by Yamaha's ride-by-wire Chip-Controlled Throttle (YCC-T). The three-processor ECU measures parameters (wheel speed, crank position, temperature, etc) every 1/1000th of a second. Interestingly, a Star-supplied chart says YCC-T also takes into account a lean-angle sensor, which, along with the standard ABS's wheel-speed sensors, could be deployed as a traction-control system. A look at our tire-melting video shows this not to be the case.
Also borrowed from Team Blue's R-series sportbikes are variable-length intake stacks (YCC-I) that use 150mm snorkels for strong torque at low revs. At 6650 rpm, the trumpets raise up to reveal shortie 54mm intakes for a V-Boost-like top-end hit that voraciously rockets the bike quickly through the gears.
Inside the motor are more sportbike-derivative pieces. Pistons are made from lightweight forged aluminum, and they rise and fall on the 180-degree crank inside ceramic-composite cylinder linings. The connecting rods are fracture-split and carburized for strength. The new combustion chamber is much flatter (a 29-degree included valve angle) and nets an 11.3:1 compression ratio which requires premium fuel. Magnesium engine covers try to keep weight down as much as possible.
Spent fuel exits into four header pipes that join in a large under-swingarm collector before flowing into a pair of four-exit mufflers with titanium skins. Inside are an oxygen sensor, two catalyzers, and an EXUP power valve.
What it all adds up to is a colossal 197 crankshaft horsepower at 9000 rpm. The final version of the previous VMax (last sold in '07) was rated at a paltry 133 hp at 8000 rpm, a whopping 48.0% less. Prodigious, too, is the new Max's torque production. Its 122 ft-lbs at 6500 revs dwarfs the 86.8 ft-lbs at 6000 rpm of the old bike to the tune of 40.6%.
There is so much power on tap that a Star rep related a story of how its rear tire was slipping on a rear-wheel dyno drum when testing its max power. Even adding a passenger didn't completely stop the slipping! I didn't manage to get him to reveal what numbers came up on Yamaha's Dynojet, but reading between the lines, we expect rear-wheel dyno figures approaching 180 hp. Note that Suzuki's B-King pumps out about 160 horses at the back wheel.
With nearly 180 rear-wheel horsepower on tap, the VMax gets down the road like nothing else on it.
The VMax's tank-mounted info panel has a display that shows how much throttle is being used, but that's the last place you'll want to be looking if the throttle is cracked more than a quarter turn. Despite being muted by a substantial 684 lbs full of fluids, 200 ponies have a way of bringing the future quickly into the present. Serious thrust is available at just 2500 rpm, and it just keeps building exponentially from there to the 9500-rpm rev limit, accompanied by an impressive and distinct V-Four yowl. The outrageous powerband is linear but explosive, so much so that the midrange opening of the YCC-I is barely perceptible - acceleration changes only from "holy s*%t! to "Hello, God!"
The VMax is fitted with a drive system that helps and hurts. Hydraulic clutch actuation eases lever effort, and gearbox throws in the 5-speed tranny are short and precise. A race-style slipper clutch works okay, but it seems a bit incongruous to be doing high-rpm downshifts on a so-called cruiser. However, this is no ordinary cruiser and, in fact, might better be labeled something like a muscle naked. Star's Warrior is correctly termed a power cruiser, and the VMax is certainly something quite different.
The VMax's rear wheel is driven by a shaft, creating some suspension issues but enhancing its tire-smoking corner-exit abilities.
While the gearbox is first-rate, the shaft-drive system partially falls on the negative side of the ledger. Focus groups may have insisted on a shaftie, but this arrangement has its dynamic compromises, no matter how well it's designed. It's heavier, so a rear suspension can't react as quick, and it also makes the bike suffer a jacking effect that results in a stiffer and higher rear end when under power.
Meet the new burnout king.
A set of 6-piston radial-mount calipers clamp down on 320mm wave discs with the assistance of standard anti-lock modulation. Note the modern headlight and scrumptious aluminum intake scoops that are polished by hand.
The jacking effect is actually quite minimal on the VMax, so kudos there, but there's no getting around the stiffer rear suspension with the throttle twisted. Bump absorption isn't as compliant and, worse, the minimal weight transfer makes this the most difficult 200-horse bike to wheelie that I've sampled! Long black darkies are typically the result of mono-wheel attempts - taller, heavier riders, who induce more weight transfer, have an easier time of it.
However, this shaft-drive byproduct has hooligan benefits of its own. Without much rearward weight transfer, the reasonably sticky 200mm Bridgestone BT028 has a snowball's chance in hell of not melting when the V-Four is given its head. If you've even been foolish enough to want to mimic the rear-wheel-sliding corner exits of pre-traction-control GP riders, the VMax stands head and shoulders above anything else on two wheels. Tire-spinning corners exits have been part of my fantasy world that rarely transfer into actuality, but Mr. Max makes them ear-to-ear-grinningly real.
In regard to the bike's ultimate acceleration, the VMax is absent a probable electronic trick and equipped with an unexpected one. First, we're thrilled to report the ECU doesn't limit power in the lower gears like on many other modern hyperbikes. Electronic intervention comes into play once 220 kph (136.7 mph) is reached, as this is the Max's top-speed limiter. However, to not handcuff dragstrip performance, the limiter is lifted to a 230-kph (142.9 mph) threshold when a quarter-mile acceleration run is sensed! For what it's worth, I saw 145 mph on the speedo before I ran out of open road.
When it comes time to shed speed, the new VMax is worlds apart from the wimpy brakes of its forbear. Up front, a four-position lever actuates a Brembo radial-pump master cylinder that feeds a pair of 6-piston radial calipers biting on 320mm wave-type discs. They proved to be very powerful but not overly sharp. A Brembo rear master cylinder powerfully fires a single-pot caliper and 298mm wave rotor, and it was when using the rear brake that I was grateful for the bike's standard ABS which isn't intrusive.
In terms of real-world usability, the VMax performs better than expected, although it's a bit clumsy at lower speeds. The narrow handlebar and cramped riding position of the old bike has been opened up by moving the grip position an inch further forward and about a half-inch taller. The seat height is listed at a modest 30.5 inches, but its broad seating area gives narrow-hipped people like me a bit of struggle to reach the ground firmly with both feet. A stepped seat-back isn't just for comfort; it's also to keep you aboard the bike during 1G acceleration.