Yzf600r
YZF600R
CYCLE WORLD TEST
YAMAHA GETS BACK IN THE THICK OF IT
A DECADE AGO, YAMAHA'S FJ600 WAS WINNING everything in sight. It was the chosen tool with which many of today's top racers cut their teeth; most notably, 500cc GP World Champion Kevin Schwantz. In 1989, Yamaha again gained widespread control of 600cc roadracing with the introduction of the FZR600. Fast, light and agile, the liquidcooled, Deltaboxframed FZR smoked anything that rolled onto a middleweight grid for two solid years. Althou the FZR600
remains in Yamaha’s lineup for ’94, its competitive racing days pretty much came to a close when Honda brought out the CBR600F2 in ’91.
Since then, diehard Yamaha enthusiasts have been biding their time. If history is any indication, their patience would be justly rewarded with a new machine that, in the spirit of the FZR and FJ before it, would stand above the competition.
Well, the ship’s come in and the 49-state YZF600R has hit the dock-California models are still a few months out to sea. Is Yamaha back in the business of winning races?
At $6999, the YZF600’s price tag would seem to indicate that all stops have been pulled out to build the ultimate 600. But Yamaha spokesmen were quick to point out that the YZF600R is actually an early-release 1995 model, which accounts for it carrying the steepest price in its class. Let’s have a look at what you’ll get for your money, here and now in ’94. The YZF’s 599cc, 16-valve, inline-Four engine improves upon the FZR powerplant in several areas. Starting with a more rigid crankcase, Yamaha engineers have made use of a lighter weight crankshaft and shortened the stroke. The YZF clutch has been beefed up with a .2 inch increase in diameter along with the addition of a pushrod bearing at the pressure plate for smoother, more reliable operation. The six-speed gearbox has been thoroughly revised with altered ratios, increased mainshaft size and heavier-duty bearings (including double bearings at the countershaft output). Gear teeth have also been widened .02 to .08 inches to handle the greater power loads of the new engine, and the gearbox is now bathed in an oil shower for greater reliability. The result is smoother, quieter gear changes than with the FZR.
Yamaha has moved away from the FZR’s caststeel cylinder liners and gone with ceramic-composite chrome-plated aluminum cylinders in the YZF, much like the plated bores used for years in their motocross engines. The advantages, says Yamaha, are reduced weight, tighter clearances and cooler running. In ’93 the AMA put into effect a standard-bore size rule for supersport racing. It would appear as though the YZF’s plated cylinder is ideally suited to such a rule, sustaining less wear over the course of a racing season.
Although cylinder-bore diameter has been increased by 3mm over the FZR, valve sizes remain the same. Included valve angle has been reduced to 33.75 degrees, down from the FZR’s 36 degrees, producing a more compact combustion chamber that retains a compression ratio of 12.0:1. In an effort to reduce valvetrain weight and increase flow, valve-stem diameter has been reduced by .5mm, now measuring 4mm. Lighter-weight lifters were sourced from the YZF750. Unique valve springs-made of an oval-cross-section wire-have reduced spring length by 3mm, raising the spring seat by the same amount, which in turn has allowed additional clearance for a straighter intake port.
Carburetor bore size has been increased, with a bank of 34mm Keihins sitting in for the 32mm Mikunis present on the FZR. Likewise, airbox volume has been increased from the FZR’s 6.5 liters to 7.7, with the inlet duct receiving increased bore and length. On its way out, spent exhaust now exits through larger-diameter headers forming a 4-2-1 system that is claimed to offer improved midrange and peak power. Radiator cooling capacity has been increased to stay in step with the new engine’s higher performance.
With the light crankshaft, engine response is quite snappy and has minimal engine-braking effect on downshifts. The motor is extremely smooth running-surprising, considering the YZF hasn’t any rubberized engine mounts. Intake noise is louder than any bike in the class. Whacking the throttle open with your chin on the tank delivers a sound that’s worth an extra 10 perceived horsepower. Fact is, the engine makes 84.6 rear-wheel horsepower—enough steam to put the YZF right in the hunt with the current top guns of the 600 class. Only time will tell, as race tuners do their magic, how much untapped potential resides within the new powerplant.
As any apex-strafer knows, the engine only amounts to half the sportbike equation. Peek beneath the YZF's skin and you’ll Find that Yamaha engineers put a good deal of effort into the new chassis. As with the FZR600, the YZF’s
Deltabox frame and swingarm are made of steel as a cost consideration. The engine is hung in the new frame, eliminating the FZR’s cradle section via use of rigid mounts on either side of the cylinder head. According to Yamaha, the YZF’s frame nearly doubles the torsional, longitudinal and lateral rigidity of the FZR’s. The Deltabox swingarm has also been strengthened without any weight gain. Wider wheels and tires turn on larger-diameter axles at both ends.
Wheelbase on the YZF is four-tenths of an inch shorter than the FZR’s, and there is revised steering geometry. Rake angle remains at 25 degrees, but trail has been increased slightly by reducing fork offset in an effort to retain stability with the shorter wheelbase. The engine has been rocked up and back 10 degrees in the frame to allow sufficient tire-toradiator clearance under full fork compression.
Similar to the CBR900RR's, the YZF fork uses a twopiece outer slider. From a distance, its gold-anodized finish gives the appearance of the latest GP legs. Spring preload is the only adjustment provided on the 41mm conventional fork. Although we would’ve hoped for more adjustability considering the bike’s asking price and ultimate mission, the fork worked plenty good on the street, providing a fairly compliant ride without bottoming over bumps during braking. A heavier spring and increased damping will likely improve its performance on the track.
We’ve been whining for years about the low-buck shock fitted to the FZR. Yamaha has seen fit to step up the program on the YZF, fitting a new shock with adjustable rebound damping. On the street we found the standard setting of seven clicks out worked well, with the ramp-type spring preload adjuster on the second step from full soft. At the track, setting the preload to the third tier and the rebound at four clicks out produced the best results for our 150pound tester. Front-end feedback was enhanced after pulling the fork legs up 10mm in the clamps. Even with the best setup we could muster, the YZF had a slight tendency to wobble through the high-speed left-right transition between Willow Spring’s Turn Seven and Eight, and in driving off some of the slower comers. Cornering clearance is extremely good; only the footpegs touched down (with the feelers removed) and then only while at the racetrack running hard on sticky race-compound tires.
Brake calipers and rotors are FZR600 items, the master cylinder coming from the YZF750/FZR1000. The reach distance to the lever is four-position adjustable, but the setting closest to the grip is still too far out for anyone with average-sized hands. The system has a very solid feel, with little initial lever travel before the pads bite. During hard stops from medium-high speeds we noticed an increase in brakepad bite as the bike slowed. Pretty strange sensation, holding a constant lever pressure and having the brakes increase their stopping power-sort of like fade in reverse. A change of pad material should clear up the problem, a simple fix.
Additional items sourced from the YZF750 include the 5gallon steel fuel tank, tailsection, instruments, throttle, switchgear, mirrors and the distinctive cat’s-eye dual-headlight assembly. Gone is the FZR’s fuel cell and its plastic dummy tank cover. Overall, the bike has the look and feel of quality.
Where the YZF truly stands out among sportbikes is in its high level of comfort, something not common among racereplica machinery. The YZF600 riding position is fairly upright-akin to that of the much acclaimed CBR600F2-the seat is well padded and there’s ample leg room. The bike feels narrow by today’s standard yet its windscreen offers the best wind protection in the class.
When developing the YZF600R, Yamaha engineers laid down three design goals; (1) Class-leading performance; (2) practical ergonomics; and (3) exciting styling. Loyal enthusiasts will be pleased with Yamaha’s latest effort. And while the YZF600R isn’t an all-conquering hero straight out of the crate-which says a great deal for the level of talent in the 600 class-Yamaha is certainly back on track.
EDITORS' NOTES
I DON’T THINK THE YZF600R WILL revert 600cc roadracing to a uni-brand show in ’94. What 1 do know is Yamaha’s latest middleweight is the most comfortable, user-friendly repliracer I’ve ridden. The riding position isn’t punishing nor is its level of engine vibration. After flogging the new YZF600R around three different racetracks at a pace much faster than I ever wish to achieve in the company of radiator grills and barbed wire, it’s clear that even in stock form, this bike’s performance envelope stretches beyond my wildest needs on the street. The YZF600R is a very good machine, easily the best middleweight sportbike the company has built to date. But the same is true for its competitors’ current offerings. 1994 promises to be an exciting year in middleweight production-based racing, I look for the YZF to be right there slugging it out for the title. Choose your weapon; if you’re looking for an advantage, 1 advise you jump the start. It’s that close. —Don Canet, Road Test Editor
YAMAHA’S FZR600 MADE ITS RACING debut at Daytona in 1989. I was there, fingers grasping chainlink fence, watching a very confident 20-year-old John Kocinski blaze from a tire-smoking, second-wave start to victory in the 600 supersport race. From my post outside of the International Horseshoe, Kocinski’s Rob Muzzy-tuned FZR appeared to be the bike of choice, for racers and street riders alike. This year, Yamaha has recruited Vance & Hines Superbike pilots Jamie James and Colin Edwards to racedebut its all-new YZF600. Their performances at Daytona, combined with those of a few talented privateers, could affect sales the same way Kocinski’s did. But motorcycles aren’t sold on race results alone. Five years ago, a brand-new FZR600 was $4899, $100 less than Honda’s CBR600. Today, the $6999 YZF600 costs $500 more than the updated CBR600F2. My advice? Buy the Honda and spend the extra cash on Kocinski how-to videos. —Matthew Miles, Managing Editor
THE WAYS OF CORPORATIONS ARE strange, and not to be understood by mortal men. Example? Yamaha. The company has come from behind in the 600 sportbike class to introduce the YZF600. It’s very well done, pretty much the measure of the class-leading Honda CBR600F2. That’s too bad. In the next year or so Honda likely will debut the F2’s replacement, and once again, everything else in the 600 sportbike class could be an also-ran. So why, one wonders, did Yamaha not indulge in a bit of Big Think and make the little YZF a technological tour-de-force that leapfrogs the competition for several seasons to come? It would have been so easy to whip on a GTS-style RADD front suspension and Omega frame, for instance. Yeah, it would have been expensive. But would it have been any more expensive than the number-two status the company seems to have resigned itself to? I doubt it. As the YZF600 sits, it’s a fine machine. But with a bit of risk-taking, it could have been a great one. —Jon E. Thompson
YAMAHA
YZF600
$6999
