Yamaha's Sportbike Gets Lighter and More Powerful

Red Bull: How can a beverage that makes you feel so good not be against the law? I find myself feeling the exact same way about the 2003 Yamaha R6. It has turned me into a shift-light junky, a 16,000-rpm user, a second-gear power-wheelie addict. The best part is that it’s available over the counter.

All-new for 2003, the Yamaha R6 has arrived on the scene to some very fierce competition from the new Kawasaki ZX-6R and Honda CBR600RR. With the ZX-6R’s inverted fork and radial brakes and the “race to street design” of the CBR, the R6 is certainly going to be kept honest.

Yamaha shaved weight from the old bike by using a new casting process that forces aluminum under high pressure into the mold. This Controlled-Fill casting process results in less porosity in the metal, making it stronger and lighter. Yamaha claims the R6’s sleek new frame has the torsional rigidity of a YZR-R7 Superbike while being more than a pound lighter. In addition, only two welds are needed to join the frame as opposed to the previous model’s 16. Attached to this is the slickest looking swingarm ever to grace a stock motorcycle. Like the frame, it is produced by the new casting process. Longer by 10mm, it is just 2.5mm at its thinnest point.

Tucked into the satin black swingarm is a new five-spoke wheel that has been lightened and strengthened. It rolls on a sticky 180/55-17 Dunlop D208 Sportmax radial and has a 220mm disc that gets worked by a two-piston caliper. I could not possibly fault the tires on the street and liked the rear brake, as there is a fair bit of lever travel before lock up. The same design that treats the spokes and the hub as one structural unit is used on the front wheel, and it rolls on a 120/60-17 D208. Twin 298mm discs, grabbed by one-piece calipers, handle braking duties. They are actuated by a five-way adjustable lever and have a nice feel for trail braking or parking lot control. Once the 4-piston calipers begin biting, though, hang on. The incredible rate in which they haul the diminutive Yamaha to a halt can border on painful.

No earth shattering changes to be found with the conventional 43mm cartridge fork, although the inner tube is now thinner. Adjustable for preload, compression and rebound damping, the stock settings are a good combination for canyon carving and freeway droning. What has been changed is the offset of the triple clamp by 5mm. Wheelbase remains the same though, because the steering head has been positioned 5mm further forward to help give the new Yamaha R6 a greater sense of stability. The front end now feels totally planted in any situation and doesn’t exhibit any nervous feeling mid-corner. Getting on the gas hard or flicking the bike side-to-side in the tight twisties is no cause for complaint either. (The previous R6s could be a little skittery under hard acceleration, so it will be interesting to see how the new bike handles accelerating over bumps on the racetrack. – Ed)

There are no major changes to the fully-adjustable rear shock. Stock settings work just fine for me, and outside of a bit of rear-end beating on some extremely rough interstate sections, there are no moans from this corner. It handles manic acceleration out of the turns with ease, and if you can induce any wobbles and weaves on public roads, you probably need to join the overachievers club or get your racing license.

Yamaha says the R6 gained three ponies over last year’s model, mostly due to the addition of R-style fuel injection. The suction-piston-style injection uses no less than seven sensors to monitor its progress. Once the fuel is in the cylinders, it is ignited by iridium spark plugs fired by new direct ignition coils. The airbox has been enlarged from 7.3 to 7.6 liters and, when pressurized by high-speed incoming air, Yamaha claims a power peak of 123 horsepower at 13,000 rpm.

Inside the engine, bore and stroke remain the same, with an increase in compression ratio and some combustion chamber reshaping to increase intake and exhaust efficiency. The intake cam now gets a little more lift and is a contributor to the increased horsepower, especially in the midrange. The cylinder is die-cast with no sleeve for reduced piston friction, better heat dissipation and a more accurate shape. The crankshaft has enlarged passages between the cylinders to reduce the fluctuation in air volume caused by the pumping action of the pistons. To further save weight and increase strength, the cylinder and crankcase assembly are a one-piece design.

All of this high-revving, horsepower-generating action builds up a lot of heat. As such, Yamaha has added a larger, curved radiator and what they call a “ring fan.” The ring seals the fan to the contours of the radiator for a claimed 10-40% improvement in cooling. It is also located to the side of the radiator so more cooling fins are hit by the oncoming air.

Exhaust gases are dealt with by a quiet four-into-one exhaust system that, like just about everything else on the new R6, has been redesigned to save weight and improve performance. Weighing in about two pound lighter than last year’s model, the system is made from a mixture of aluminum and titanium. The double-walled header pipes are reshaped for reduced noise and smoother flow, and they send exhaust gasses to the single muffler that includes a catalytic converter. Yamaha says the R6 surpasses the new EU2 standards with no loss of power.

Visually, the bike is simply stunning from any angle, and made for a photographer's dream during some beautiful sun-filled days out in the California canyons. Slicker-looking bodywork with new “engine revealing side cowls” and a more compact tail section compliment the Gatling beam multi-reflector headlights. The net result of all these changes is improved aerodynamics as well as looking mighty fine. Wind protection isn’t too bad, with most of the blast being taken square in the chest of my six-foot body. This worked nicely on the highway, as it took some pressure off my wrists and shoulders. Get into a tuck and the wind goes clean over you, with the mechanical symphony being played out underneath your chest being the dominant sound.

The view from the cockpit is clean and uncluttered, and the instrument control panel is very compact and efficient. The white-faced tachometer is augmented by a shift light that lets you know it is time to select another gear when it lights up at 14, 250 rpm. The speedometer is digital and has a temperature gauge above and an odometer and tripmeter below. There are a couple of trip options available, and I even managed to figure out how to use the select and reset buttons so it can’t be too hard. Below the gauges is a row of warning lights, and the whole plot gives off a warm glow at night. Tres chic. The view from the mirrors is typical of a sport-orientated bike, so it’s necessary to tuck in an elbow to get a good look behind.

Acceleration in top gear is quick if not rapid, but once over the legal limit the little 6 takes off like a scalded cat without so much as a downshift. Drop to second at this speed and you will find yourself looking at the sky. Around town, you can run the rpm as low as you like, and the perfect fuel injection will let you open the throttle anywhere, anytime, without missing a beat. Of course, everything starts happening a lot quicker once you pass 8,000 rpm, and the bike pulls hard till redline.

(Editor’s note: Content Manager Ken Hutchison was able to briefly sample an R6 test bike at Bike Week, and he reports that the Yamaha seems to lack the midrange steam of the new CBR600RR and 636cc ZX-6R. Also, he says, “The transmission was clunky and cantankerous compared to the ultra-slick CBR tranny. Yamaha got caught with their pants down here.”)

The footpegs are now 5mm further forward for better weight distribution to the front end. They are certainly high and the bars are low, but I found the overall ride package a lot more comfortable than I had believed it would be. You are not going to want to go touring on this thing, but do not despair if your favorite set of twisties is a few hours away. I did not keep much of an eye on gas mileage, although I can tell you the fuel light came on at around 120 miles after some serious throttle abuse in the deserted canyons.

So, the new R6 is lighter (8 lbs.), more powerful and better looking while still costing the same $7,999. It’s definitely a better bike than its predecessor, but it has some stiff competition with the new ZX and CBR. The ultimate winner can’t be decided until we ride these things back to back, which will have to wait until our 600 shootout.

Meanwhile, I’m off to get some therapy, or at least a support group that can understand my deranged ramblings about shift lights, 16,000 rpm, and second-gear power wheelies. I am trying to get over the separation anxiety that has plagued me since turning the bike back in to Yamaha, as well as the need to hear the four cylinders howling while the road gets sucked toward the fairing in fast forward.

Nothing I have ridden can be so mercilessly thrown into corners with such confidence, and nothing I have ridden has left me so badly wanting more. But until my local Yamaha dealer starts taking in kids or dogs on trade, I guess I’m stuck with Red Bull.