The hooligan of this crew was once again the nimblest on the track, though it comes at a price. Kawasaki has tamed the ZX's front end a bit, but the addition of a steering damper would have made some of us less less nervous. Roberti was unperturbed and set his quickest time on the rowdy ZX.
The ZX is the wild animal of the group, and whether that's off-putting or desirable is up to you.
While the CBR was deemed rider friendly, the ZX-10R is rompin' ready. Its compact riding position received the highest scores in this test, and each time it was taken out on the track it was accompanied by mouth-watering anticipation and a healthy level of respect. It plays high-proof tequila to Honda's wine cooler.
"Last year the ZX wooed me to the dark side with raw power and the promise of feeling like a superhero waiting at the apex of every turn," says the comic-book minded Hutchison. "This year it feels more stable thanks to its revised suspension, but it's still a handful on the track."
Once again, the Kawasaki is the only one of the group not to be equipped from the factory with a steering damper. The 10R's suspension modifications outlined in our street test calmed the bike's nervousness under acceleration, but the test notes from our riders all mentioned a hesitancy to make full use of the ZX's stunning power.
"Laying down huge doses of power as you roll on the gas, the front end wants to lift even though you are still laid over," Chamberlain warns. "It's not a huge deal until you combine the light front end with rough pavement and a lack of a steering damper. Then you get headshakes."
"I never got a violent headshake," says Hutchison, "but it definitely let me know it wanted to get crazy on me."
Roberti noted the ZX's riding position, which he deemed "too high", might be contributing to its tendency to unweight its front end, as we noted during dragstrip testing in our street test. This condition results in a rider being unable to use full throttle in parts of the two lowest gears.
"You definitely have to be careful with this thing because it can quickly get out of shape on the throttle," Becklin adds. "The motor is strong enough to wheelie just about everywhere - even at high speeds."
What the lightest-in-class ZX-10 lacks in stability it makes up for in unrivaled agility. This is the sharpest-steering tool of the group, and it never has any trouble tightening its line. This was especially notable in PIR's tight infield section, where the max g recorded was second only to the amazing Ducati.
The ZX-10R's motor is no less impressive in the face of the new Gixxer. It managed to out-class the competition down the back straight at PIR, clocking the quickest trap speed of 168.2 mph.
Helping corner entries is the ZX's slipper clutch, which greatly eases downshifts by limiting compression braking, known in mechanical terms as "back-torque." The system, a first on production literbikes last year and now joined by the Suzuki for '05, allows its rider to be less concerned about perfectly matching revs when downshifting we had enough to worry about inside PIR's concrete walls. Interestingly, the ZX exhibited more compression braking from its motor than did the slipper-equipped Gixxer.
Our Vbox showed the ZX-10R to have the highest trap speed on the front straight thanks to its mighty motor, just edging the equally powerful GSX-R with an actual 168.2 mph. The Kawi's radial-mount brake calipers and petal-shaped discs bled off 100 mph in time for Turn 1, exhibiting strong braking that was judged by our riders to be right up with the best four-cylinder bikes. However, the Vbox data from Roberti showed the ZX actually pulled less g under braking than the rest. Your mileage may vary.
What this all adds up to was Roberti's quickest time around PIR. And despite all our wussy concerns about headshake, our fastest guy experienced none.
It's fair to say the Kawasaki is one of our favorites to ride thanks to its nuclear reactor motor, scythe-like handling and a willingness to go out and play - up to a point. When it came time to extract the next couple of tenths around the track, the rest of us had some trepidation about cracking its throttle to its stops. Those of us without the courage and smoothness of Roberti lapped quicker on other bikes.
"This bike is a rocket but really needs a steering damper to complete the package," says Becklin, no slow guy himself. "The front end is just too nervous on the gas to make the rider feel confident it isn't going to ruin his world."
"Although the ZX is as good as or better than the other bikes in every other way, the lack of this simple-bolt on accessory is enough to keep it from the top of my score sheet," BC says succinctly.
