2009 Yamaha YZF-R1 - The Game Changer

Yamaha's Crossplane Crankshaft Changes Everything

By Aaron Frank, Photography by Paul Barshon

Yamaha's newest YZF-R1 sounds nothing like an inline-four. The syncopated growl instead suggests an extremely high-revving V-4. It doesn't feel like an inline-four, either. A bit throbby at idle, vibration actually decreases as you near redline. And it applies power to pavement better than any production four we've ridden, coming off corners with the steady thrust of a traction-controlled Superbike. Just like that, everything we thought we knew about literbikes has been turned upside-down.

Ever since Honda's archetypal CB750 appeared 40 years ago, every production inline-four has used a 180-degree crank. A pair of pistons arrives at the top of the stroke every 180 degrees, and combustion events occur precisely 180 degrees apart. Such predictability makes it easy to manipulate intake and exhaust harmonics for max power, but--especially on large-displacement bikes--the resulting crank speed fluctuations can compromise rear tire grip and feedback.

Crank speed is not constant with a conventional crankshaft. Starting and stopping each relatively heavy piston/connecting-rod assembly twice per crank revolution--at Top Dead Center and Bottom Dead Center--creates a pattern of micro-accelerations and decelerations that Yamaha calls inertia torque. This inertia torque travels like a micro-shockwave through the powertrain until it manifests as a shake or vibration at the rear contact patch, degrading grip and rideability.

Yamaha claims its Crossplane crankshaft technology--developed on Valentino Rossi's YZR-M1 MotoGP racer and making its production debut on the new R1--effectively eliminates inertia torque-induced "noise" at the rear tire. Crossplane crankpins are positioned 90 degrees apart, so a piston arrives at TDC/BDC every 90 degrees, compared to every 180 degrees with a conventional crank. As a result, two pistons maintain high speed as the other two are reversing direction, stabilizing crank speed. Reducing crank speed fluctuations reduces the power shake at the rear contact patch, resulting in smoother power delivery, improved traction and enhanced rideability.

The Crossplane crank is far from the only upgrade to the sixth-generation R1. The chassis has been completely revised to better exploit the improved traction and power delivery characteristics, the suspension has been modernized with more tricks from Rossi's racer, and the aerodynamic package has been retooled, too. It's a radically different machine, with more than enough changes to justify a 15-hour flight across the Atlantic for the official debut at Eastern Creek Raceway outside of Sydney, Australia.

From the saddle, the '09 R1 feels more compact and inviting than before. Reach to the bars has been shortened 10mm, and the saddle is relocated 7.6mm farther forward. Footpegs are now adjustable up and down as well as fore and aft. The new upper fairing seems more compact, too, an impression that was reinforced later while howling down Eastern Creek's 150-mph front straight. I noted a bit more buffeting when my helmet wasn't firmly mated to the tank.

The new R1 feels smaller and lighter, too, despite the fact that weight has climbed to a claimed 454 pounds wet, up from 436 last year. The magic of mass centralization effectively masks that extra 18 pounds. A stubby tail and shorty mufflers (now supported by a lightweight magnesium subframe) cut pounds far from the mass center, and the motor is angled 9 degrees upward and moved forward 8.2mm to allow the fuel tank to sit lower in the frame. These alterations, along with an optimized 52.4/47.6 percent fore/aft weight bias, help maintain responsive handling.

Some of these extra pounds can be traced to the Crossplane powerplant. The 90-degree crank demands a counter-rotating balance shaft to dampen its inherent vibrations, adding weight and sapping power by an estimated 3 percent. The new exhaust weighs more, too, at least on U.S.-spec bikes that require an additional mechanical baffle to comply with our more restrictive noise limits. Yamaha preemptively warned us that American-spec R1s will make about 6 fewer horsepower than European models due to this choked-up exhaust and a mild ECU change. "Paging Chuck Graves..."

There's still plenty of power available from the now-shorter-stroke engine (low- to mid- 150s, our intui-dyno is guessing), and anyway, Yamaha's power-enhancing YCC-I variable-length intake tracts, along with shorter overall gearing (now 17/47, compared to 17/45), help hide any deficit at street speeds. But raw numbers hardly describe the Crossplane's real advantages. Horsepower is useless without grip--witness modern Superbike racing's dependence on traction control. Whatever the Crossplane engine gives up in peak power, it more than pays back with smoother delivery and improved grip. For most of us, this will go much farther than an extra 10 ponies ever would.

You feel the Crossplane advantage in every part of a turn. Reduced engine braking is one byproduct, and on the downhill entry to Eastern Creek's first-gear Turn 9, it's a revelation. Without excessive compression braking pulling the bike in the opposite direction--and aided by Yamaha's excellent, ramp-type slipper clutch--the R1 zips toward the apex with the immediacy of a 600, the rear wheel obediently and ever so slightly drifting out behind. With less rear wheel input bossing the chassis around, you can brake harder into a corner without worry of overwhelming front grip.

A confident front end makes it easier to exploit the R1's newfound stability. The Soqi fork is all-new for '09 and, just like the MotoGP bike's, splits compression and rebound damping into separate fork legs for more consistent performance. Eastern Creek's Turn 2--a first-gear wake-up call coming at the end of a 140-mph straight--provided a good opportunity to assess front-end performance under heavy braking. No matter how hard I clamped on the reshaped front brake lever (boosted by a revised lever ratio for improved modulation), the fork maintained compliance and kept the front tire in full contact with the tarmac.

Smoother power delivery let the engineers reduce the lateral stiffness of both the chassis and swingarm, resulting in increased mid-corner stability, especially at extreme lean angles. Knee down through the bump-riddled Turn 4 sweeper, the R1 held a line like Gorilla Glue, leaving plenty of neurons free to anticipate the exit--and corner exits are where the new R1 shines brightest. A new, more progressive bottom-mount rear suspension link--another piece of pirated M1 technology--prevents squat and helps the bike hook up and hustle out. The R1's enhanced traction-grabbing abilities were especially evident during the afternoon sessions, when mechanics levered on mega-grippy, triple-compound Michelin Power One DOT race tires. With the front tire now grazing the tarmac on nearly every exit, we were suddenly thankful for the new electronically boosted steering damper that amplifies damping force any time the throttle is more than 50 percent open.

The final piece of the R1 rideability equation is the "D-Mode" toggle on the right-hand switchgear that jumps between three preset power profiles on-the-fly (provided the throttle is closed). The comprehensive gauge package includes both engine mode and accelerator opening angle indicators to help you navigate the system. "Standard" is the default mode, delivering an approximately 1:1 ratio between twistgrip and throttle slide movement. Taking full advantage of Yamaha's YCC-T electronic throttle activation, A-mode accelerates by 30 percent the rate at which the throttle slides open between zero and 50 percent throttle. Switching to A-mode is dramatic, if not overwhelming--we found the standard setting more than adequate, power-wise, and much easier to modulate. B-Mode blunts throttle response by 30 percent at all throttle angles. This was a surprisingly useful setting in the late morning, serving as defacto traction control after sizzling track temps reduced the standard Pilot Powers to a hot, slick mess. (Dunlop Sportmax D210s are standard fitment for U.S. bikes.)

It's a rare opportunity nowadays to ride a new model as radically changed as the '09 R1. The Crossplane crankshaft completely redefines the character of the inline-four engine and, initially at least, you can't stop noticing how different everything sounds and feels beneath you. After a few laps, though, you stop noticing; then the biggest impression is how transparent the R1 becomes. The Crossplane engine makes the R1 easier to ignore than ever before--and that's a compliment of the highest degree. It's so much easier to read what's going on at the rear contact patch because all the typical distractions--noise, vibrations, peaky power delivery--are diminished. The usual sensory inputs are muted, leaving even more attention available to focus on riding the bike. Yamaha's Crossplane crankshaft changes everything--for the better.

Hard Parts
New from the crankshaft up

Bodywork
Sophisticated bodywork does more than just cover up the ugly bits. The lower fairing cowl is now composed of separate inner and outer shells engineered to more precisely control airflow around the bike at high speeds. This so-called "Active Air Management" system is designed to force cool air into the radiator and more efficiently suck hot air out of the engine bay, eliminating the need for hot-air vents at the sides of the radiator and thus improving aerodynamics. Radically enlarged ram-air ducts dominate the upper fairing. New headlights are the latest two-stage projector beams, and both remain lit in high- and low-beam operation, ending annoying "Hey buddy, your light is out" conversations for good. This year's shorter, tighter tailsection is designed with mass centralization in mind.

Electronics
Yamaha's signature electronic technology remains intact, including YCC-I chip-controlled intake runners that snap from a low end-boosting long position to a shorter, top-end enhancing length at 9400 rpm. Ride-by-wire YCC-T throttle activation remains, powered by a 32-bit ECU that separately maps each cylinder's ignition and fuel injection. The YCC-T technology also drives the R1's new D-Mode function that enables the rider to adjust performance characteristics according to three preset drive modes. Unlike Suzuki's similar S-DMS system, which alters power delivery via changes in ignition and injection timing, D-Mode simply alters the speed at which the YCC-T system opens the throttle plates. In addition to the standard setting, there's also an accelerated "A" mode for sharper throttle response and a "B" mode that softens response.

Chassis
The Deltabox aluminum frame has been completely redesigned to complement the Crossplane powerplant. A gravity-cast headstock/front engine mount connects to a gravity-cast rear section with frame rails formed using Yamaha's controlled-fill die-casting process, balancing vertical, lateral and torsional rigidity to improve stability at lean. According to Yamaha, vertical rigidity is increased by 22 percent, lateral rigidity is decreased by 37 percent and torsional rigidity is reduced by 2 percent. Controlled-fill casting technology also forms the one-piece magnesium subframe, shaving precious poundage far from the center of mass. The swingarm, consisting of a gravity-cast main section fitted with CF-cast spars, has likewise been retuned for 28 percent more vertical rigidity, 21 percent less lateral stiffness and 29 percent less torsional twist resistance--all to exploit the additional available traction. Geometry remains essential identical, though, with the same rake (24.0 degrees) and trail (4.0 inches). Only the wheelbase--just 5mm shorter--has changed. Finally, a taller 55-series rear tire helps the new R1 turn-in a bit more quickly.

Suspension
A new Soqi fork isolates compression and rebound-damping functions, with the left leg dedicated to the former and the right to the latter. This independent arrangement simplifies suspension adjustments, improves response and stability over changing surfaces, and eliminates the dead zone where conventional forks transition from compression to rebound action. A Soqi shock offers high/low-speed compression damping and the added convenience of a hydraulic spring-preload adjuster, which adjusts with an Allen wrench instead of a spanner (or hammer and punch). This new shock rides on a new bottom link-type rear suspension, identical to that on the M1 racer, said to make more complete use of the full suspension stroke. Featuring a more progressive leverage ratio, this linkage provides improved small-bump compliance in the beginning of its travel and firmer resistance to big inputs.

Engine
Excepting Ducati's Desmosedici RR, no other production sportbike so closely resembles its MotoGP forebear as the new YZF-R1. Crossplane crankshaft technology comes directly from the YZR-M1 racebike, with each crankpin located 90 degrees from the next (instead of the conventional 180) to decrease inertia torque. Technically this is not a "big-bang" motor, which fires pairs of cylinders simultaneously, but rather a "long-bang" design with an uneven (270-180-90-180) firing interval that offers a degree of the big-bang's traction-enhancing benefits with less vibration and top-end power loss. Displacement remains at 998cc, but the bore has increased 1mm (to 78mm), and the stroke has been shortened accordingly (to 52.2mm, from 53.6mm). Otherwise, engine geometry is essentially identical to the '08 model. Fracture-split connecting rods drive forged pistons inside friction-reducing ceramic composite-plated cylinders, while titanium intake valves slash reciprocating mass. For the first time, the R1 gets secondary, showerhead-type fuel injectors to better fill its 45mm throttle bodies, improving throttle response and high-rpm power. The EXUP valve has been deleted from the titanium exhaust and a more efficient, three-way catalyst replaces last year's two separate catalyzers.

Tech Spec

EVOLUTION
Yamaha's flagship sportbike gets a new, MotoGP-
derived motor with the unique, 90-degree Crossplane
crankshaft.
RIVALS
Japan's latest literbikes: Honda CBR1000RR,
Kawasaki ZX-10R and Suzuki GSX-R1000.
TECH
Price $12,390-$12,490
Engine type l-c inline-four
Valve train DOHC, 16v
Displacement 998cc
Bore x stroke 78.0 x 52.2mm
Compression 12.7:1
Fuel system Mikuni EFI
Clutch Wet, multi-plate slipper
Transmission 6-speed
Claimed horsepower 178.4 bhp @12,500 rpm
Claimed torque 84.5 lb-ft @ 10,000 rpm
Frame Aluminum twin-spar
Front suspension 43mm Soqi inverted fork with adjustable
spring preload, compression and rebound
damping
Rear suspension Single Soqi shock with adjustable spring
preload, high/low-speed compression and
rebound damping
Front brake Dual Sumitomo six-piston radial calipers,
310mm discs
Rear brake Single Nissin one-piston caliper, 220mm disc
Front tire 120/70-ZR17 Dunlop Sportmax D210F
Rear tire 190/55-ZR17 Dunlop Sportmax D210F
Rake/trail 24.0 deg./4.0 in.
Seat height 32.9 in.
Wheelbase 55.7 in.
Fuel capacity 4.8 gal.
Claimed wet weight 454 lbs.
Color Team Yamaha Blue/White, Raven/Candy Red,
Pearl White/Rapid Red, Cadmium Yellow/Raven
Available Now
Warranty 12 mo./unlimited mi.

Contact:
Yamaha Motor Corp. USA
6555 Katella Ave.
Cypress, CA 90630
800.962.7926
www.yamaha-motor.com

Verdict 4.5 stars out of 5
The most effective, accessible and charismatic literbike we've ridden yet.

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