Superbikes For the Street
Superbikes For The street
CW COMPARISON
FAST FREDDIE AND THE SUPERSPORT 750s
DISPLAYED BEFORE YOU IS SPORTBIKE NIRVANA. THEY ARE the 750 Supersports, those dynamic, hard-edged platforms from which Superbike championships are born. This year, more so than in the past, the class is bulging with talent.
Kawasaki's ZX-7 and the limited-edition ZX-7R are accomplished veterans with numerous race wins and championships to their credit. Honda's RC45 and Yamaha's YZF750R are new to the fold. Providing additional spice is Suzuki's revised GSX-R750, and rounding out the field is Ducati's 888LTD, which, despite having two fewer cylinders, performs on par with the Japanese Multis. For our comparison, Road Test Editor Don Canet and reigning World Endurance Champion Doug Toland were joined by three-time World Roadracing Champion Freddie Spencer. The 32-year-old Louisiana native is best known for his 250 and 500cc GP titles, but his background in Superbike racing is
extensive. During his brilliant AMA career, Spencer has raced everything from Suzukis, Ducatis and Moto Guzzis to Kawasakis and a variety of inlineand V-Four Honda Superbikes. Exploring the outer handling limits of these machines in a street environment is asking for trouble; guardrails loom large at triple-digit speed, and "But your Honor, we were testing," won't
sail in court. So for this go-fast gathering, we headed to Willow Springs International Raceway and its unnervingly fast 2.5-mile, nine-turn roadcourse. To equalize traction, we had California Sportbike Racing fit each bike's wheels-including the Honda's unorthodox 16-inch front rim-with street-com pound Metzeler ME Zi radials. The CSR crew also helped with suspension adjustments and, when necessary, made swift tire changes at the track. Before we pull aside the CW Curtain of Secrecy and reveal our choice for this year's best street Superbike, let us intro duce the participants, arranged in alphabetical
DUCATI 888LTD
Ducati's 888LTD (formerly known as the 888SP0) is mechanically unchanged for '94. Several aesthetic changes, however, have been made. Carbon-fiber fenders are fitted front and rear, and the 17-inch wheels are now bronze in color to match the paint on the bike's multi-tube chrome-moly spaceframe. Footpeg brackets and controls are black-anodized, and each bike wears a numbered triple-
clamp plaque. A $100 price increase brings the Ducati's cost to $13,600, making it the second-most expensive bike in our comparison. The 888LTD weighs in at 451 pounds dry, three pounds more than the lightest bike in this test, the Honda RC45. In terms of engine per formance, though, the Ducati is at the other end of the spectrum,
producing 10 less horsepower than the class-leading ZX-7R. Still, the fuel-injected, dohc, eight-valve Twin is the torquiest engine of the bunch, producing a staggering 60 foot-pounds at 7000 rpm, which helps to explain its impres sive performance numbers. All three riders praised the Ducati, especially its high-speed stability, cornering prowess, and top-line fit and finish. "Terrific right out of the box," said Canet. "It's the most stable bike in the group, and it’s able to hold a tighter line than anything else.”
“Nicely finished and refined,” said Toland, who turned the quickest lap time of the six on the Ducati, a 1:31.42. “Everything works like its supposed to. You don’t have to think about doing anything except riding it. Ground clearance is very good.”
“It’s very well balanced,” added Spencer. “You can change lines anywhere in a comer. I’ve heard about weight distribution problems on this bike-that it would be top heavy and push the front-but that wasn’t the case. The engine is really responsive and smooth. And compared to the other bikes, the Ducati feels more like a 250. Most people would probably go faster on it than anything else. It’s really easy to ride.”
PRICE
HONDA RC45
Only 50 examples of Honda's all-new RC45 are slated for U.S. distribution, a good number of which will probably be Street licensed. For Honda, the $27,000 machine is an expensive formality in the homologation process, which, it hopes, will result in Superbike championships both here and abroad. With its 55.4-inch wheelbase-only the Kawasaki ZX-7R is as compact-and tight steering geometry, the RC45 is very sensitive to rider inputs. "Right away, it reminded me of the RVF750 I raced at Suzuka two years ago," relayed Spencer. "The RC45's
steering is very quick and responsive, but it's also very stable. The faster you go, the better it likes it." Regular track testers Toland and Canet were also impressed with the Honda's crisp handling. "It steers where you want it to go," said Toland. "The front end shakes a bit over Turn
6 (a crowned, high-speed right-hander taken at full lean), but it doesn't limit the bike's ability to go fast. The brakes are great-consistent with good feel and feedback." "The chassis feels short, and pitches fore and aft more than others," said Canet, who set quick lap on the Honda. "Even so, the front end feels totally planted."
The Honda's 749cc, 90-degree V-Four is a new, more-compact design, and features right-side
cam-gear drive, composite cylin der sleeves, and pre-set fuel d
injection. Fitted with a European-spec electronic control unit (ECU),
the engine produced 102.6 horsepower at 12,000 rpm and 49.5 foot pounds of torque at 10,000 rpm, good enough for an 11.44-second quarter-mile and 157-mph top speed. "The Honda and Ducati are similar in that they both come off corners well," said Toland. "It's very responsive to throttle inputs," added Canet. "That (throttle response) can make a big difference in how a bike handles," Spencer noted. "Throttle control affects steering and weight transfer. Good throttle response can make up for other deficiencies."
ToP SPEED
For all its virtues, the 448-pound RC45 was fourth quickest at the racetrack, eclipsing the high-speed circuit in 1:31.97, a half-second behind the front-running Ducati. Still, testers were extremely impressed with the Honda. "A lot of streetbikes handle well until you try to make them into a racing machine," Spencer said. "This will be just the opposite. Without a doubt, this bike has the most potential."
KAWASAKI ZX-7
Excluding minor graphics updates, the Kawasaki ZX-7 is unchanged for '94. Last year, the ZX-7 won our three-bike 750 comparison, nudging out the limited-edition YZF750SP and revised GSX-R750. Though its steering was noticeably heavier than that of Suzuki or Yamaha, the '93 ZX-7's chassis delivered excellent control and feedback, enabling the 499-pound machine to rail
around the Willow Springs roadcourse in an impressive time of 1:32.1. Engine performance was also noteworthy last year. The 16-valve, inline-Four produced 104.3 rear-wheel horsepower at 11,000 rpm, and made 52.6 foot-pounds of torque at 8750 rpm. This year, things were not as good. At the dyno, the sup posedly unchanged ZX-7 made 99.6 horsepower at 11,500 rpm and 50.6 foot-pounds of torque at 9000 rpm. Things were also different at the racetrack. Though steering remained high-effort and the chassis offered good feedback, complaints of less-than-perfect carburetion and a lack of rebound damping at the rear hurt the ZX-7’s lap times, the best of which was a 1:33.17, the slowest of the six.
“The front end feels more planted than the YZF750's, but the shock needs more rebound damping,” said Canet. “It holds its line well, and doesn’t wag its head like the Yamaha. The engine has a broad spread of power, but last year’s bike was faster.”
“It’s really stable at speed,” said Toland. “But quick transitions require significant input on the bars. By dropping the front end a bit and adding more preload at the rear, I think we could have seen 1:32s.”
“The ZX-7 is a good-handling streetbike,” commented Spencer. “It’s stable and forgiving, but the faster you ride it, the more you feel its flaws. I liked the brakes, though. They provided very good feel, and didn't fade.”
QUARTER-MILE
KAWASAKI ZX-7R
Like the RC45, the ZX-7R is a racer in street togs. More specifically, this is Kawasakis Superbike starter kit, a $10,699 limited-edition model-$2600 more than the standard 7-that boasts an aluminum fuel tank, 39mm flat-slide Keihin carburetors (instead of the ZX-7's 39mm CVs), a close-ratio gearbox and a rider-only tailsection. And where the ZX-7's suspension components are adjustable for
spring preload and rebound damping, the ZX-7R's fork and shock also have compression adjusters. Those changes do make a difference, both in weight and perfor mance. On CW's certi fied scales, the ZX-7R weighed in at 461 pounds dry, 38 pounds less than the ZX-7 and only 13 more than the Honda. At the dyna mometer, the 7R was an
absolute beast, pumping out 105.2 rear-wheel horsepower and 53.3 foot-pounds of torque. Dragstrip performance was less encouraging. Hindered by its tall first gear, the ZX-7R recorded a best run of 11.23 seconds at 128.54 mph. Top speed was 157 mph. For all of its street-going faults, though, the Kawasaki was in its glory at the racetrack. With Canet at
the contols the ZX-7R was third quickest overall at 1:3 1.94. "The ZX-7R's carburetion is much more responsive than that of the standard 7," said Spencer. "That
alone gives it an edge. The chassis is very for giving, and the extra performance makes it easier to slide around." "There is a dip in the power curve at about 9000
rpm," said Toland. "It's most noticeable in fourth, fifth and sixth gear when there's an
increased load on the engine. By the time you hit 10 grand, though, A
it’s full speed ahead.”
“I wouldn’t recommend it for the street,” said Canet,
“but as racebike, well, its reputation speaks for itself.
The ZX-7R feels as if it’s in the same league as the Ducati and Honda, but it takes more effort to go as fast. It works very well.”
DRY WEIGHT
SUZUKI GSX-750
Suzuki's revised GSX-R750 was this year's surprise. Changes to the bike center around weight reduction, in both the chassis and the engine. Dry weight was reduced by a shocking 31 pounds via changes in frame-wall thickness, the addition of magnesium valveand sidecovers, and the use of hollowed transmission shafts and machined transmission gears. Chassis alterations include thin-wall 43mm fork tubes, a bridged swingarm, altered suspen sion rates, and a wider rear wheel and sixpiston front-brake calipers sourced from the GSX-R 1100. Where the ’93 GSX-R750 felt softly sprung and vague at the limit, the revamped machine is rock solid. According to Suzuki, damping rates have been increased substantially, which, in addition to a compact, nonadjustable steering damper, has dramatically improved chassis stability. Steering is light, neutral and precise, and the liquid-cooled, 16-valve, inline-Four pulls harder and revs to its 13,500-rpm redline with newfound gusto. On the dyno, the top-end-biased engine produced 99.9 horsepower at 11,000 rpm and 51.9 foot-pounds of torque at 9500 rpm.
“Engine performance is great,” said Spencer. “The GSXR’s engine is more responsive than that of the ZX-7R, and it pulls through the rpm range with less effort. High-speed stability is excellent, noticeably better than the ZX-7R. There’s a lot of damping in the front end, but it absorbs the bumps really well. Weight distribution is good, and the brakes didn't fade." "The GSX-R was really smooth and stable," said Canet. "To me, it definitely steered lighter than last year's bike. It
TOP GEAR ROLL-ONS
was obvious just riding down pit lane." The GSX-R may have performed well enough to turn a best lap of 1:32.20 and blast through the quarter mile in 10.75 sec onds (quickest of the six), but its ergonomics were the least favorite. Reaching the han-
diebars requires a lengthy stretch, and its seat-to-footpeg rela tionship is nothing short of torture, even on the racetrack. "It was the most uncomfortable bike I rode all day," said Spencer.
YAMAHA YZF750R
The YZF750R represents Yamaha's long-awaited reentry into the 750cc sportbike market. Due to its street intent, the R-model does without the Euro SP version's flat-slide carburetors and close-ratio gearbox, but everything else-aluminum Deltabox frame, fully adjustable KYB suspension and bridged swingarm-remains intact Powering the YZF is a dohc, 749cc, 6 valve, liquid cooled, inline-Four. A quartet of downdra 38mm Mikunis feeds the engine, which produces 99.3 rear-wheel horsepow
er at 11,500 rpm. Peak torque is 52.2 foot-pounds at 9000 rpm. Both figures are on par with the other in line Fours, yet the Yamaha managed the day's secondquickest lap time, a 1:3 1.67. Quarter mile and top-speed performances were also impressive. The YZF sprinted through the traps
in 10.77 seconds at 128 mph, and charged to a top speed of 155 mph. "The engine made pretty good power,~' Toland said. "But it felt really flat. That's not bad, it's just deceptive because you don't feel like you're going fast." Early in the day, the YZF's front end would shudder under hard braking, tainting rider confidence. A cocked or improperly bedded-in brake pad might have been the culprit, but by late afternoon, the problem worked itself out. Minor headshake was the only other criticism.
“The Yamaha shook its head pretty good cresting Turn 6,” said Canet. “I cut my best laps when I pulled myself up over the gas tank, putting more weight on the front end, which made it track better. I thought the front end felt less planted than anything else in the group. The rear suspension worked really well, though.”
Dropping the YZF’s front end 10mm helped, but didn’t completely cure the problem.
“Once the machine is accelerating, it doesn’t matter if the head shakes,” Spencer remarked. “As long as the rear end is hooked up, you can put up with that movement.”
For Toland, who set the Yamaha’s best lap, headshake wasn’t a concern.
“It would twitch a little here and there, but for me, the front end hooked up pretty well,” said Toland. “Overall, the suspension seemed nicely balanced.”
BRAKING
CONCLUSION
In one meena, of them, what are have performance we learned? specials. These Indeed, bikes, with every a tallast ented rider and the necessary tweaks, every one of them could take the grid at Daytona. On the street, all six are in their element on early-morning blasts through tightly configured canyons, or over sweeping mountain passes.
p^formance-per-dollar is your yardstick, then the $8099 GSX-R750 is a winner. Clearly, the Suzuki’s light weight
Am^reuS1Vie Performance ar,d price make it a viable choice’ And the identically priced ZX-7? Call it a not-so-close second' At the next level, in terms of cost, are the $10,699 Kawasaki R and $9799 Yamaha YZF750R. Both are impressive motorcycles, though the Yamaha is a better streetbike. With its street-oriented carburetion and transmission, the YZF can commute, sport-tour and even endure the occasional dragstrin grudge match with aplomb. While the same can’t be said of the Kawasaki, its racing pedigree includes AMA and World uperbike championships and a Suzuka 8-Hour victory Will
uIaTuha pr°Ve aS comPetitive? We’ll have to wait and see. Which brings us to the most expensive-and exclusive-members of our Supe^îTort Club, the Ducati 888LTD and the Hondci RÇ45. If potential is a factor, the Honda is arguably the best platform from which to build a top-line, race-winning Superbike. But with a base price of $27,000, the road to vic-
Dnri’f *z7ryf'g flFSt StepAt half the COSt of the RC,
Ducät! s 888 is faster around a racetrack and easier to ride And while it may be expensive compared to the other inlineours, the Ducati’s broad spread of power, slick handling
s unning good looks and ear-pleasing exhaust music are worth every penny.
In AMA~a~id Vorid Superbike racing, Italy's 888 has gone to best Japan has to offer and come away the winner. And that's just what it's done here.
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LAP TIMES, WILLOW SPRINGS RACEWAY
