Sportbike riders are all about the numbers. Numbers are objective, and we like that because they put a measurable value on the things that appeal to us about sportbikes: power, weight, acceleration, speed. And we can rattle those numbers off like a baseball fan talks statistics. "This bike puts out x horsepower, that bike weighs y pounds, and my bike goes z mph." One number can make or break a bike's sales record, even if actual performance is far superior in other categories than the one represented by just that single measurement.
Let's talk about some numbers related to the two bikes tested here-the '08 Kawasaki ZX-14 and Suzuki GSX1300R Hayabusa-and put them in perspective. Suzuki's '07 GSX-R1000 posted a peak of 158.2 horsepower on our SuperFlow dyno. The Hayabusa makes more than the GSX-R's peak across a 2500-rpm band-almost a quarter of its rev range. Kawasaki's ZX-10R made the most torque of last year's literbikes, measuring 76.4 ft-lb in our shootout. The ZX-14 tops that number-at 3500 rpm, the lowest reading we could get on the dyno. How about thrust, the actual driving force delivered to the rear wheel? In first gear Honda's CBR1000RR makes 775 pounds, more than any other literbike. The ZX-14 and Hayabusa don't quite make that much-in second gear. In first gear, though, they have 30 percent more thrust. You get the idea: These bikes are stronger than literbikes in more ways than peak horsepower numbers alone can show.
We've already sampled the Hayabusa ("Higher 'Busa," Jan. '08) and ZX-14 ("Meaner and Greener," Mar. '08), and those stories outline the full details of each bike's update. But we've been aching to pit them against each other ever since the Geek came back from the intros all googly-eyed with stories of butt-puckering speed and arm-stretching acceleration. What we found after a couple of weeks of flogging is that even though the two bikes share almost identical performance numbers, they couldn't be more different.
You'll notice that difference from the moment you sit on them. Both feel oil-tanker huge after riding a comparative speedboat 600, but the Kawasaki's higher clip-ons and narrower seat make it easier to reach the ground and maneuver in a parking lot. The ZX-14's seat is plusher and, combined with the more upright riding position, makes it more comfortable for longer periods. The Hayabusa has Suzuki's typical-of-late high/forward peg position and low/close clip-ons; if you're comfortable on any of the GSX-Rs you'll feel right at home here. Both bikes start and warm up quickly and easily, although our ZX-14's fairing buzzes at high idle. While the Hayabusa's bodywork fits tightly and looks sleek, we're not looking forward to finding all the hidden fasteners when it needs to be removed.
Around town it's a toss-up as to which bike is our favorite. Both are surprisingly a bit soft below 3500 rpm ("soft" being a relative term when you consider that at that rpm the 'Busa and ZX are making more torque than a Ducati 1098 does at its peak) but will idle away from a light with little effort. Both run warm in town and spill hot air on your legs, even on cool days. And both have clunky transmissions that can feel like big parts are moving around inside-as they surely are. The Suzuki is characterized by crisp throttle response, light, neutral steering and brakes that are numb at low speeds. The Kawasaki feels just as peppy but steers heavily at low speeds and has one-finger brakes that are easily modulated. Either bike would be fine for the daily grind.
When it comes to a longer freeway commute, the ZX-14 is clearly preferable. More upright ergos, softer suspension and a comfy seat make running through a tankful of fuel relatively painless. Surprisingly neither bike impressed us with wind protection; the Suzuki's low screen allows more of the windblast to hit you but with little buffeting. The Kawasaki's taller, narrower screen makes for more buffeting, especially on your shoulders. The dual-counterbalanced ZX motor is smoother than the Hayabusa's single-counterbalanced mill. At less than 4500 rpm the Suzuki is almost as smooth, but above that mark it shakes enough that you'll want to limit cruising speed to a single-point ticket rather than a misdemeanor. Range on both bikes is about equal. The ZX-14's poorer fuel mileage and larger tank give a maximum of 168 miles compared with the Hayabusa's better mileage and smaller tank that equate to 182 miles (175 with the California model's even smaller tank).
Aggressive canyon runs will reveal more disparities between the bikes. The Kawasaki's suspension, plush and soft in town and on the freeway, allows the bike to pitch about and even bottom over rougher pavement. The Suzuki's stiffer boingers may make for a more jarring ride on the freeway and in town, but you'll welcome their composure in a rutted-out sweeper at triple-digit speeds. We didn't need to mess with the Hayabusa's suspension much, but it seemed we were constantly changing the Kawasaki's to juggle geometry, pitching and bottoming.
Crisp in town, the Kawasaki's powerful binders slow its 567 pounds from the entirely unexpected speed it's capable of generating on any straight-no matter how short-quickly and with little fanfare. The Hayabusa's brakes are wooden in comparison, requiring a good squeeze and offering little feedback. Part of the difference is in the number of pads in each caliper-two for the Suzuki, four on the Kawasaki-but the ZX-14 has an up-to-date radial-pump master cylinder, where the Hayabusa also sports a conventional unit. It's not a good place to be cutting corners on a flagship sportbike capable of doubling a typical freeway's speed limit from a standing stop in less than eight seconds.
Kawasaki ZX-14
Test Notes
+ Great bottom-end and midrange power
+ Crisp, powerful brakes
- Soft fork and awkward steering
- Notchy throttle response
x What the first-gen ZX-14 should have been
Suggested Suspension Settings
FRONT
Spring preload: 3 lines showing; rebound damping: 9 clicks out from full stiff; compression damping: 6 clicks out from full stiff
REAR
Spring preload: 12mm thread showing; rebound damping: 0.25 turn out from full stiff; compression damping: 0.5 turn out from full stiff
Suzuki Hayabusa
Test Notes
+ Great top-end power
+ Solid chassis with light steering
- Wooden brakes
- Vibrates at more than 4500 rpm
x Refined but not redefined
Suggested Suspension Settings
FRONT
Spring preload: 6 turns out from full stiff; rebound damping: 4 clicks out from full stiff; compression damping: 7 clicks out from full stiff
REAR
Spring preload: 6mm thread showing; rebound damping: 10 clicks out from full stiff; compression damping: 8 clicks out from full stiff