Kawasaki ZZ-R 1100 

D-Model

The D-model capitalizes on Kawasaki's good idea in its sealed air intake system. They've added an air tract on the nose of the fairing to increase the ram-air effect. The airbox is nearly three litre bigger to take the extra wind. Kawasaki reckon the system is 100% more effective. and adds, we estimate, as much as ten horsepower to the bike at top speed.

The changes to the D-model begin with the frame. Which is now of welded stamped sheet alloy rather than extruded box section. It's been redesigned with the intention of making it stronger. Kawasaki must've felt it needed more muscles -  The swingarm's torsional rigidity is up 58%. This redesign has increased wheelbase by 15mm. The steering geometry is actually more relaxed (for high speed stability) with rake going out half a degree to 26.5 and trail 4mm up to 107mm. In contradiction, it actually feels a little more willing to change direction, compared to the '92 model. The only thing I can point to is the change in weight distribution achieved by a new, three-litre larger tank shape which places the bulk of fuel under yer goolies, lowering the centre of gravity. Overall dry weight is up 5kg. The rear wheel now takes a 180/55-17-section tyre; last year's was a mere 170/60-17.
 The disc brakes are 1cm larger at 320mm on the front.

FEW MOTORCYCLES GENERATE AS much excitement as the Kawasaki ZX-11. None generate as much speed. When it was introduced in 1990, the big ZX posted a top speed of 176 miles per hour, making it the fastest production motorcycle Cycle World had ever tested.

Three years later, the newly revised 1993 ZX-11 is claimed to be even faster. At the bike's world press launch in Phoenix, Arizona, our pre-production ZX-11 registered an indicated top speed of 180 miles per hour before we ran out of road and had to shut down. Take off maybe 10 mph for speedometer error, but remember this was at an altitude of about 2000 feet. Back down at sea level and with a long enough run, a true 180-plus mph is likely.

Top speed aside, what really is amazing about this motorcycle is how hard it accelerates in any gear, and at practically any rpm. Despite a claimed dry weight of 514 pounds, when the throttle is rolled on, the ZX lunges forward, its engine screaming towards its 11,500-rpm redline. Our bike did exhibit a minor stumble if the throttle was whacked open below 4000 rpm, but above that mark, the engine was very responsive.

But this is not a motor that must hover near redline to please its pilot. Rather, the liquid-cooled, dohc, inline-Four is quite happy spinning easily at lower rpm, delivering smooth, nearly vibration-free power. This is most apparent cruising around town, or at freeway speeds, where the engine is merely loafing along, though rocketship performance is still just a tug on the twistgrip away.

Two factors contribute to the bike's impressive performance. Sleeker, more aerodynamic bodywork has been fitted-along with new ducting, a taller, wider windscreen and a new fuel tank that increases fuel capacity by nearly one gallon to a total of 6.3 gallons. Secondly, the bike has been equipped with Kawasaki's new Twin Ram Air induction system. A. pair of oval-shaped openings, located directly below the headlight, provide the 16.9-liter sealed airbox (20 percent larger than last year) with its only source of fresh air. As with the previous single inlet design, the openings serve as simple compressors, boosting airbox pressure and with it, power.

As speeds increase, the fuel-to-air ratio provided by the quartet of 40mm Keihin semi-downdraft carburetors leans out slightly. To compensate, the float bowls are vented through a single breather line routed around the airbox to the intake openings. This allows float-bowl pressure to rise in equal proportion to airbox pressure, so that the appropriate amount of fuel can be administered. In simple terms, the faster the bike goes, the more power its engine is able to produce. At normal cruising speeds, though, there is little gain, other than the claim of improved throttle response.

Complementing the new intake system is an updated exhaust. The mufflers are now 30 percent larger to increase exhaust flow. So as not to limit ground clearance, the leading edges of the bigger canisters have been beveled. In addition, all production ZX-lls, including U.S.-spec models, are now fitted with Kawasaki's Clean Air System, which mixes outside air with exhaust gases for a more complete combustion process and lower exhaust emissions.

The only other engine-related change involves the oi) coo)er, which has increased thermal capacity. Otherwise, the rest of the transversely mounted, 16-valve engine, with its gear-driven counterbalancer and leftside cam drive, is unaltered. The over-square 76.0mm bore and 58.0mm stroke remain, as does the 30-degree included valve angle, 11.0:1 compression ratio, hydraulically actuated clutch and six-speed transmission. Claimed output is 147 horsepower, an increase of two horsepower from the previous version.

But the ZX-U's engine is not the bike's only attribute. Earlier models were considered terrific all-round performers, with sporting-yet-comfort-ah)e ergonomics and impressive handling characteristics. After spending the better part of two days aboard the '93 ZX-11, we found it to exhibit the same qualities.

The sport-oriented riding position, dictated by its low-set handlebars, rearset footrests and deeply sculptured one-piece seat, is plenty comfortable for sport-touring, yet feels right when attacking in the twisties. Given a preference, we would like to see more padding in the seat, which can wear a little thin towards the end of a long ride. Passenger accommodations are impressive, with plenty of saddle area, a stylish handrail and reasonably located footrests. Instruments, including a new fue) gauge, a coo)ant-tem-perature gauge and twin resettable tripmeters, are easy to read. Adjustable hand levers, a lockable storage pocket located to the left of the cockpit, and four retractable bungee-cord hooks add to rider convenience.

Of even greater importance, though, is the ZX-11 's new twin-beam frame. Fabricated from pressed-aluminum sheet, the main frame spars are welded to a cast steering head and swingarm pivots, making it, according to Kawasaki, not only stronger and more rigid than the old extruded-aluminum frame, but also 3.5 pounds lighter. Swingarm rigidity has also been improved, with a new, stronger alloy casting at the arm's mounting point.

In addition, the frame's steering geometry has been altered for improved high-speed stability. Rake was increased one-half of a degree to 26.5 degrees, and trail has been lengthened to 4.2 inches, an increase of one-tenth inch. Those modifications have also affected the bike's wheelbase, which now measures 58.9 inches, up slightly from the previous 58.3 inches.

These changes have resulted in phenomenal stability, which is especially noticeable at high speeds. Surprisingly, though, the new geometry has not hurt the bike's nimbleness. While a firm hand is required to initiate a turn, most noticeably in a series of tight esses, the' bike meets its desired lean angle with impressive ease, and requires little effort to remain firmly planted on its chosen line.

Contributing to this performance are the new ZR-rated Bridgestone Bat-tlax BT-50 E radials. Fitted to 3.5- and 5.5-inch-wide, 17-inch aluminum wheels, the 120/70 front and 180/55 rear have been specially designed for this model, and feature stiffer carcass construction and greater sidewall strength to handle the weight and potential speeds of the bike. Reportedly, the compound is between that of a full-on race tire and a standard street Battlax. In approximately 600 miles of hard riding, the tires showed only minor wear, and offered excellent traction in both dry and wet conditions.

Braking has also been updated, thanks to new 12.6-inch semi-floating front discs, up four-tenths of an inch from last year. Besides their increased size, the new rotors feature a revised hole pattern for greater swept area. We found that repeated hard stops Trom speeds in excess of 100 miles per hour will still cause the brakes to fade, but once the fluid is allowed to cool, the system returns to its otherwise high level of performance. At the rear is a single 9.8-inch disc brake with a full-floating opposed-piston caliper.

Like the engine internals, the 11 's suspension has been left unchanged The conventional 43mm KYB fork is adjustable for spring preload and four-way rebound damping, as is the linkage-mounted KYB rear damper. We found both units to be appropriately sprung and valved for fast sport-riding. Although the ride still feels a bit stiff around town, even for those who weigh over 200 hundred pounds. the firmness adds to the bike's superior stability at high speeds.

Now, the all-important question: Is the new ZX-11. with its numerous changes, worth $300 more than the old-stvle 11. which will also be avail able in '93 at a price of S849Q? We believe so. The incredible top-end rush, excellent chassis, improved fit and finish, and nicely done graphic-treatment make the new ZX-11 even more of a world-beater.

In the process, Kawasaki has widened the bike's appeal, especially to those who are searching for a premium all-around sportbike. albeit one with a penchant for speed. O