Yamaha Yzf-R6

YAMAHA YZF-R6

Sharpening the tip, Supersport-style

DON CANET

WHEN YAMAHA INVITED THE MOTO PRESS DOWN UNDER FOR the launch of its first YZF-R6 back in 1999,I returned home very impressed. Not by the ride along Australia’s Great Ocean Road; we have our own majestic Pacific Coast Highway right here. Nor was it the feast of indigenous mystery BBQ served up by our hosts; Burger King would have sufficed just fine. No, it was the R6’s impressive performance lapping the famed Phillip Island Grand Prix circuit that knocked my socks off.

To prove a point, I raced a bone-stock R6 at the AMA Supersport National in Daytona a few months later. The purpose of the project was to show how incredibly good a modern supersport 600 is right off the showroom floor. It’s a point that has grown even sharper with the latest YZF-R6.

Although the premise of “Taking Stock” ( Cycle World, June, 1999) was to race an unmodified R6, I’d fitted the bike with a steering damper in the interest of personal safety. I bring this up only because having just ridden the all-new ’03 model at a recent world press launch in Spain, the latest R6 may be stable enough to hit the high banks without a damper.

Reviewing Yamaha’s engineering goals for the revised R6 reveals the following objectives: 1) Improve sharpness and stability; 2) improve handling at deep cornering angles; and 3) increase agility. Achieving gains in both agility and stability presents a challenge, in that one is often traded for the other. Yamaha worked its magic through mass-concentration around the rolling axis. Putting its revolutionary CF die-casting process to good use, the completely new Delta Box III frame boasts a whopping 50 percent increase in torsional stiffness while weighing less. The frame is cleverly comprised of only two pieces, joined by a pair of welds visible at the base of the main spars. How good is that? Some 16 welds were needed to tack together last year’s frame. The swingarm and bolt-on rear subframe benefit from the CF treatment as well, both being lighter and stiffer than previously possible.

Lighter five-spoke wheels, alloy suspension link and more-compact rear brake caliper have shaved unsprung weight. Other small details, such as the aluminum muffler’s titanium internals and a lightweight LED taillight assembly, all add up to centralizing mass, the sum of which equates to a quicker-handling package. Claimed dry weight is down to 357 pounds, 11 less than last year.

CW RIDING IMPRESION

Wheelbase remains at 54.3 inches, even though a few key items have been shuffled about. Said to offer improved traction, the swingarm is now 10mm longer. But its pivot point is located 10mm farther forward and higher on the frame to maintain the same wheelbase and droop angle. Moving the pivot closer to the countershaft sprocket also has the benefit of reducing the torque effect the drive chain has on the rear suspension when power is applied.

Although trail has been increased 5mm for added stability, wheelbase is unaffected because the steering head is now 5mm farther forward to compensate for a 5mm reduction in triple-clamp offset. The seating position and footpeg location have also moved forward 5mm, placing more weight on the front. This all translates to a greater sense of stability through the bars. Shimmy and shake have been reduced considerably.

In fact, the only serious headshake I experienced during the two-day press intro was my own noggin waggin’ in disbelief as former GP hero Randy Mamola slipped past on the brakes and showed me what an R6 is truly capable of. Mamola’s move took place at the Circuit of Almería, where I was joined by fellow American, British and Swiss journalists for the R6 world press launch. Located due south of Madrid just off the Spanish Mediterranean coast, this 2.5-mile, 15-tum road course features a trio of tricky blind crested curves, a couple of quick side-toside transitions between comers, a tight flip-flop chicane and plenty of hard braking. The track surface is very smooth and grippy-perhaps too sweet a medium to experience the R6’s broad capability.

Before cutting us loose on the race course, however, we spent a day on the local mountain roads and highways. Right out of the hotel drive, I could sense improvement in the R6’s rideability. A host of changes to the engine have resulted in improved power delivery, >

throttle response and shifting action, making the R6 not only a more potent track tool, but also a better street-riding platform. Certainly the switch to fuel-injection steals the headlines, and I’m happy to report the R6 offers the same sensual throttle control we raved about a year ago when the R1 shed its carburetors. Comes as no surprise really, since the 38mm throttle bodies delivering the vertical downdraft shot to the R6’s four-valve cylinders employ the same ingeniously simple CV-operated slides as the Rl. A redesigned airbox that’s slightly larger in capacity and less restrictive than before is fed by reshaped ram-air ducts.

Increased lift on the intake cam is a main contributor to the engine’s power gains, felt primarily in the midrange and over-rev areas of the output curve. The claim is now 123 peak horsepower, 3 up on the first R6. New pistons with thicker skirts on the intake side run in sleeveless ceramiccomposite-coated cylinders. The top piston ring has also been altered to reduce oil consumption. Below is a reshaped crankshaft that’s more precisely balanced. I can vouch for the engine’s smooth-running character; vibes only just became noticeable above 8000 rpm.

Tweaks to the shift mechanism and redesigned gear dogs on several gears have made for improved shift action that is both lighter and quicker. In two days of flogging, I didn’t experience a single missed shift.

All the motor’s improved manners make it that much easier to focus your attention on the task at hand: the road. The R6 has always been light-handling, if not the most surefooted of current supersports. Now, it may just offer the best of both worlds. While still boasting almost telepathic steering response, requiring only a moderate amount of effort applied through the clip-on bars to initiate a turn, the revised chassis geometry and suspension have substantially improved the bike’s stability.

I made a wrong turn along the street route and ended up traveling several miles along a road more suited to a dualsport intro. While I can think of a number of machines I’d rather have been hustling through the seemingly endless series of tight, gravel-strewn curves, the impeccable throttle control afforded by the R6’s digital fuel-injection made the going nothing less than fun. What’s more, the bike’s suspension, while taut enough for the most hardcore sport duty, proved surprisingly compliant along this ragged stretch of tarmac.

I rode the first track session the following day with the standard suspension settings. Even with this softly damped setup, the R6’s handling and abundant cornering clearance allowed a level of aggression and comer speed well beyond a sane street pace. Turning the damping adjusters in several clicks offered improved feedback and reduced the weight pitch I’d experienced under hard braking or acceleration.

Having Mamola on hand to chase offered another level of adjustment-riding with a legend will assuredly sharpen one’s skills. I found myself digging deeper and pushing the Michelin Pilot Sport radiais to their limits when the man was near. Good stuff, though; the R6 simply did what I asked of it, never faltered and held my intended line. Front brake feel was excellent, with all the stopping power I could ask for. Throttle response was ultra-crisp at all times. This allowed confidence and control when modulating the gas while leaned over full-tilt, sparks flying from the footpeg feeler through one of the trickiest crested curves you can imagine.

It’s difficult to fathom the YZF-R6 can get much better than it is right now. It’s even harder still to imagine it would really need to. Perhaps one of the other competing 600s due for release this year will have something to say about that?