[motorcyclistonline.com - first rides] - 2008 Yamaha YZF-R6 - First Ride

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2008 Yamaha YZF-R6 - First Ride
2008 Yamaha YZF-R6It was dj vu, like the man said, all over again. For the second November in a row the U.S. press corps disembarked at Laguna Seca Raceway to make laps aboard the latest Yamaha sportbike. Last year we sampled the redone YZF-R1, a fearsome machine that left us crying for mommy after just a few laps. This year we returned to ride the baby-brother YZF-R6, and the experience couldn't have been more different.

The overwhelming R1 mocked us at every corner, daring us to open the throttle to the stop and then terrifying us whenever we screwed up the courage to try. The R6, on the other hand, proved an excellent and unflappable companion. Made even fizzier for 2008 with the YCC-I variable-length intake tracts and other trickle-down R1 technology, plus an all-new chassis that lets you further exploit its surgical-sharp steering precision, this latest R6 seemed a perfect match for the undulating Central California circuit. You expect dj vu to inspire boredom in the "haven't-we-been-herebefore?" sense. The shrieking 600 inspires anything but, and instead provided one of the most viscerally stimulating track experiences yet.

Skeptics question the validity of tracktesting motorcycles, and wonder what useful information can be gleaned. In the case of the R6, a track test tells us everything we need to know. The 600 has come to represent the thin edge of the wedge with regard to track-specific hardware, and Yamaha is unapologetic about its latest middleweight being even more trackbiased than before.

The technical presentation began with a cascade of demographic data. Supersport sales are up 52 percent in the past six years, with R6 sales growing by 44 percent. More to the immediate point, there's been a 42 percent increase in the amount of racetrack miles ridden by the average supersport owner over the past two years, with an 86 percent increase among R6 owners. When Yamaha made the '06 R6 into a more track-focused machine, some worried less all-around capability might hurt sales. This data suggests the exact opposite. So when it came time for Platform Manager Kouchi Amano to design the next-generation R6, the brief called for it to be more aggressive in every respect.

Though it looks essentially identical to the '07 version (the bodywork is only slightly revised), the '08 is actually an all-new motorcycle with a lighter, more agile chassis, a stronger, more sophisticated engine, stiffer, track-specific suspension and a more aggressive riding position. Don't like the sound of that? The kinder, gentler $8299 YZF-R6S is still in the '08 lineup for the non-apexobsessed. The '08 R6 is built to rule the racetrack, and if you're the sort of aggressive, experienced track-day rider Yamaha identified in its design brief, you'll likely be pleased with the changes.

Last year's R6 offered the highest-revving engine in its class (even after accounting for the overly optimistic tach), and also the most potent top-end rush, at the expense of midrange power. Soft on power anywhere below 10,000 rpm, the '07 R6 required a quick left foot and a concentrated effort to keep the engine on the boil. Thus, pumping up midrange power was Job 1 for '08. Engine Development Manager Nobuharu Takahashi called for a number of changes to increase torque output, including higher-compression pistons, a largerdiameter header crossover pipe and, most substantially, grafting on the YCC-I chip-controlled intake system that utilizes longer, 66mm intake funnels to maximize low- and midrange torque production and shorter, 26mm funnels for an even more fierce top-end hit.

Yamaha claims the benefit of this system is even more pronounced on the smaller-bore R6 than on the R1, and after riding it, we agree. While no horsepower or torque claims were made, a spokesman did show us comparative dyno curves that suggested the '08 R6 makes similar low-end power compared to last year, but significantly more midrange power as well as a flatter, broader curve from 12,000 rpm up. This feels valid at speed: It's still a slow train to Slugville under 6 grand, but the bike now pulls strongly from 6000 rpm all the way up to the 16,500-rpm redline. It should be noted that the pitch change in the intake howl that occurs at 13,700 rpm, when the intake funnels snap from the long to the short position,is absolutely hair-raising, making this one of the most aurally stimulating sportbikes we've ridden.

Throttle response is instantaneous and flawless thanks to a revised version of Yamaha's revolutionary YCC-T Fly By Wire throttle that electronically modulates throttle input to provide seamless throttle action. A new antiengine-braking ECU circuit keeps the throttle butterflies cracked under heavy deceleration to aid the slipper clutch in keeping the rear wheel from locking during aggressive corner entries. The first few times this system activated, at the entrance to Laguna's hard-braking Turn 11 or the Corkscrew, it was startling-it feels almost as if you failed to close the throttle completely and the bike is still accelerating slightly against the brakes. Once you get accustomed to this sensation, however, the system proves exceptionally effective. Hacked-out, tire-howling corner entries are way too easy on the '08 R6, making us look (and feel) much more competent than we really are. Better living through electronics.

The chassis has been completely redesigned this year as well, with spring rates increasing slightly at both ends (2.5 percent front/5 percent rear) and a new frame that is slightly less rigid to better communicate what's happening at the contact patches. The rider now sits farther forward and lower thanks to re-angled clip-ons mounted 5mm lower, improving forward weight bias and enhancing turn-in and corner grip. Suspension is four-way adjustable, allowing riders to dial in a set-up sensitive enough to soak up small bumps but stiff enough to resist bottoming.

Handling is markedly improved. We found the last-gen R6 to be somewhat nervous,turning in too quickly for our tastes and sometimes requiring mid-corner corrections to stay on line. This year's version, with stiffer, betterbalanced suspension and slightly increased fork offset, transfers weight more progressively under braking and acceleration, making it easier to control. When you need to change your line quickly-as you do at least twice per lap at Laguna, in the double-apex Turn 2 and, of course, the Corkscrew-the more forward weight bias makes the '08 bike more responsive to steering inputs.

With even lower bars than before, the R6 requires a certain amount of athleticism to ride-a touring bike it's not. Yamaha staff did suggest a novel way to improve rider comfort,however, at least for casual riders who are less concerned about outright handling precision. Thanks to extra ride-height adjustability added this year, the front of the bike can be raised and the rear lowered slightly to effectively shift the weight bias rearward and take pressure off the rider's wrists without impacting handling too badly.

As mentioned previously, the bodywork was reshaped in subtle ways to freshen up the look without abandoning the familiar (and popular) styling. The ram-air inlet is enlarged slightly and the mirrors are relocated to the upper mounting stay to improve airflow over the fairing. A lower fairing vent was removed and some mounting hardware was hidden to clean up the aerodynamics on the bottom half, while the tailsection was re-shaped to make the passenger pad look more "wing-like." The licenseplate hanger is a quick-detach assembly to simplify track-day or racing prep, and other track-ready touches include a built-in lap timer controlled by the right handlebar switches and a programmable shift light.

These latter points will undoubtedly be appreciated by core R6 enthusiasts who increasingly expect race-ready performance from Yamaha's premier 600cc-class offering. Our initial track test suggests these riders will be rewarded, as we were during our most recent visit to Laguna Seca. Dj vu, it turns out, isn't always as we remember it.

Tech Spec
Evolution
An even more aggressive, track-focused version of last year's already uncompromising R6.

Rivals
The usual suspects: Honda CBR, Kawasaki ZX-6R, Suzuki gSX-R and Triumph's Daytona 675 triple.

TECH Price: $9599-$9799 Engine type: l-c inline-four Valve train: DOHC, 16v Displacement: 599cc Bore x stroke: 67.0 x 42.5mm Compression: 13.1:1 Fuel system: Mikuni EFI w/YCC-T and YCC-I Clutch: Wet, multi-plate slipper Transmission: 6-speed Claimed hp: na Claimed torque: na Frame: Aluminum twin-spar Front suspension: 41mm Soqi fork with adj. preload, high/low compression and rebound damping Rear suspension: Soqi shock with adj. preload, high/low compression and rebound damping Front brake: Dual Sumitomo four-piston radial calipers, 310mm discs Rear brake: Single Nissin one-piston caliper, 220mm disc Front tire: 120/70-ZR17 Dunlop Sportmax Qualifier Rear tire: 180/55-ZR17 Dunlop Sportmax Qualifier Rake/trail: 24.0/3.8 in. Seat height: 33.5 in. Wheelbase: 54.3 in. Fuel capacity: 4.6 gal. Claimed dry weight: 366 lbs. Color: Team Yamaha Blue/White, Raven, Liquid Silver, Cadmium Yellow w/Flames Available: Now Warranty: 12 mo., unlimited mi.

Verdict
A clear improvement over last year's somewhat wheezy, slightly nervous-handling R6.

2008 Yamaha YZF-R6
Hard Parts
Engine
Yamaha made more than 50 engine changes for '08 to improve the high-revving R6's power and durability. Direct-plated ceramic-composite cylinder bores dissipate more heat and reduce frictional losses, as do wider connecting-rod bearings and new crank-journal bearings with increased oil flow. A more convex piston dome boosts compression from 12.8:1 to 13.1:1. The Mikuni EFI system has had its mapping revised to improve cylinder filling and features a quartet of 41mm throttle bodies. A primary injector located below the butterfly is paired to a showerhead-type secondary injector, activated at 6000 rpm. Directignition coils, dual-electrode sparkplugs and a high-output magneto deliver accurate, reliable firing, and combustion byproducts are evacuated through a stainless steel header and gP-style under-engine muffler containing triple exhaust catalyzers and an O2 sensor. A titanium EXUP exhaust valve located upstream from the muffler broadens the powerband by managing exhaust pressure resonances, and a titanium silencer trims a bit more weight.

Electronics
Fly-by-wire throttle activation-aka YCC-T-provides seamless response on the '08 R6. A conventional push-pull cable operates an Accelerator Position Sensor located on the throttle body bank,which communicates via the ECU with a Throttle Valve Drive Motor that electronically controls the butterflies for optimal response under any riding condition. New to the R6 this year are the YCC-I variable-length intake funnels that debuted on the R1 last year. The intake funnels measure 66mm in the tall position (35mm taller than last year's fixed 31mm funnels), substantially boosting torque production and enhancing low- and midrange power. When the motor reaches 13,700 rpm (with over 60 degrees of throttle opening) an electronic motor instantaneously snaps the funnels to the short length of 26mm (5mm shorter than last year) for more responsive high-rpm acceleration.

Frame
The R6 Deltabox aluminum frame is new for '08, combining a thicker cast headstock and stiffer cast motor and swingarm mounts with new spars made from pressed-aluminum plate to shave weight and optimize rigidity. Yamaha reports that vertical rigidity has been reduced by 4.6 percent and torsional rigidity by 2 percent-changes that, along with a deleted crossmember, improve front-end feedback and handling response. A die-cast magnesium subframe-a first for Yamaha-shaves 1 pound from high up on the chassis, improving mass centralization and lessening turning inertia. A new swingarm has likewise been tuned for optimal rigidity, with internal ribbing added to a thicker cast pivot section (that mounts higher on the frame for increased anti-squat effect) and spars that are now forged instead of extruded. These changes result in a claimed 11 percent increase in vertical stiffness and a 9.1 percent increase in torsional rigidity, to improve traction for better acceleration out of corners.

Suspension/Brakes
Suspension is four-way adjustable front and rear, with high- and low-speed compression damping at both ends, setting the R6 apart from its classmates. The 41mm inverted fork is now held by a wider lower triple clamp to increase torsional rigidity and front-end feedback, while the outer legs have been extended 10mm to allow greater ride-height adjustability. Stiffer fork springs (9.0 kg/mm, up from 8.8) better resist hard braking, and the shock spring is also firmer (10.5 kg/mm, up from 10.0) to balance the stiffer front springs. A 7mm ride-height adjuster has been added to the shock as well to increase chassis adjustability and accommodate the use of taller, race-profile tires. Radial-mount four-piston front brake calipers are unchanged save for slightly thicker rotors (5mm, up from 4.5mm) for improved heat dissipation.

Clutch/Transmission
The close-ratio six-speed transmission is unchanged from '07, as is the back-torquelimiting slipper clutch. The effectiveness of the slipper clutch is even more pronounced in '08, however, thanks to a new anti-engine-braking ECU circuit. This system keeps the throttle butterflies cracked open slightly during high-rpm deceleration, further reducing engine braking for improved chassis stability during aggressive corner entries.


Photo Gallery: 2008 Yamaha YZF-R6 - Motorcyclist Magazine



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