Yamaha Yzf600
YAMAHA YZF600
'94 PREVIEW
HOW TO HEAT UP THE 600 CLASS
MOTORCYCLING’S HOTTEST LEAGUE JUST GOT A NEW player, one that seems likely to greatly enliven not only Yamaha showrooms, but also 600cc supersport racing.
The new player is Yamaha’s YZF600. It’s a long-over-due stablemate for the trusty old FZR600, alongside which it will be sold in 1994. The FZR600 once owned 600cc supersport racing. But lately the bike-a product of FJ/FZ600 lineage and basically unchanged since its 1989 introduction-has had its hands full. Certainly it continues to sell well; Yamaha spokesmen say the company moves more than 5000 FZRóOOs per year. But out where the rubber meets the racetrack, the bike is finishing behind its more contemporary competitors from Kawasaki, Honda and Suzuki. This new bike is intended to change that. Indeed, if there’s any surprise associated with this new player-which will retain FZR600 nomenclature in Europe-it is that Yamaha will wait until summer of 1994 to introduce it as a 1995 model.
Yamaha spokesmen attending the YZF’s world introduction in Paris in late September told Cycle World that the bike is completely new, and owes nothing to any other bike in the Yamaha line. It is a tidy, compact machine that reflects a finely drawn set of compromises: On one side, it is meant to be light, powerful and rigid. On the other, it is meant to be commercially competitive at a time when prices are being adversely affected by the strength of the yen against the dollar.
This need to balance price against performance is the reason the YZF is built around not an aluminum Deltabox frame, but a steel one with a detachable rear subframe. This compromise seems of minimal significance, as the bike’s claimed dry weight is 405 pounds, a pound less than the claimed dry weights of the FZR and the Honda CBR. Of course, the ’93 FZR’s actual measured weight with a dry fuel tank is 430 pounds-one more than the actual weight of
the CBR600F2, and 32 less than that of the Kawasaki ZX-6. It’ll take a real-world weigh-in to see how the YZF measures up to the other class contenders.
Certainly the YZF600 looks to have the engine specifications it will take to hang with the class front-runners, though as a concession to cost, it uses four valves per cylinder instead of five. This is an all-new, non-EXUP, liquidcooled, dohc Four breathing through a quartet of 34mm
Keihins to produce a claimed 98 horsepower from a bore/stroke of 62 x 49.6mm. The engine is mounted at a 35degree forward slant, and its power production gets some
help from a sky-high 12:1 compression ratio made possible in part by a very narrow, 17-degree included valve angle. It also gets help from a neat piece of high technology that involves use of ceramic-composite plating on the cylinder walls. This is intended to provide increased wear resistance and better heat transfer and to allow tighter piston tolerances. Yamaha says use of the coating allows higher power production than would be possible in a similar engine without the cylinder coatings.
Front suspension is another area in which the cost-performance ratio was carefully studied. While inverted forks were considered, Yamaha looked at the wildly successful Honda CBR900RR-equipped with a conventional fork-and shelved the upside-downers. A conventional fork typically is less expensive than an upside-down unit, and therefore assisted in the company’s battle to hold the YZF’s price down. The preload-adjustable fork uses 41mm tubes and a two-piece, screwed-together lower section styled to resemble an upside-down fork. Steering geometry is moderately quick, with a steering-head angle of 25 degrees and 3.8 inches of trail. At the rear, a shock with adjustable preload and rebound damping works through a steel swingarm.
Wheels are painted aluminum-the front is 3.5 inches wide and is fitted with a 120/60 radial, the rear is 5 inches wide and wears a 160/60 radial boot. Front stopping power is provided by two 11.7-inch discs gripped by a pair of four-piston calipers, while at the rear there’s a 9.6-inch disc and a two-piston caliper. All this runs on a wheelbase that stretches 55.7 inches-about l/2 inch shorter than the FZR’s. Though the bike is fairly compact, it is remarkably roomy-indeed, it uses the same 5-gallon fuel tank as the YZF750, and is styled to closely resemble that machine.
Though Yamaha worked very hard to keep the YZF600’s costs down, its U.S. retail price-not yet set at presstime-still will be at the upper end of the 600cc sportbike spectrum. In Europe, the goal was to match the price of the YZF’s principle rival-the CBR600F2-exceeding the Honda’s number by no more than 5 percent. It seems reasonable to expect a similar pricing strategy here, which would peg the YZF at about $6500.
Whatever the bike’s final sales price, it seems set to deliver good value per dollar, and to raise the intensity levels in the 600cc sportbike league, in showrooms and on racetracks.
