Cycle News - Archive Issues - 1990's

AIDING ·IMPRESSION. 1996 Kawasaki ZX·7R By Colin Fraser Photos by Tom Riles ~ • awasaki knew it would have its work cut out for it in 1996. This new year is a major one in terms of new sportbikes, and Kawasaki obviously wishes to maintain its position at the front of the pack. In the past few years, Kawasaki has built an enviable racing history, and its new street machines will be expected to carry on that tradition. Kawasaki's existing 750-dass sportbike, the ZX-7 series Supersport and Superbike racing platform, has achieved considerable success. Since its most recent revamp in 1993, this Ninja has taken the World Superb ike Championships for "Team Green," as well as giving Kawasaki their first-ever triumph at the prestigious Suzuka 8-Hour endurance race. Scott Russell's three Daytona 200 wins are also an important part of the ZX-7's heritage. So the time was right for another update. For 1996 the Kawasaki 750ccclass sports lineup gets a complete make-over, even though the inja ZX7R and ZX-7RR still bear a close family resemblance to the earlier model range. Kawasaki was not coy about its performance ambitions with the latest Ninja: "This is the machine with which we plan to regain our World Superbike Championship title," explained Marketing and Sales Manager Hilo Matsumura of the ZX-7RR The easiest way to spot a 1996 Ninja are the huge, twin ram-air scoops on either side af the twin headlights, replacing the previous left-side-only duct. Both '96 models will be most recognizable in their "Muzzy replica" paint scheme on the reworked bodywork, with green fairings and tanks, purple tail sections, and purple wheels. White number-plate sections provide a splash of contrasting color without going to the gaudy graphics route. A solo seat and lack of rear footpegs distinguish the RR from the more passenger-friendly single R version. The R is also available in an attractive, glossy red finish. In previous years, the R designation referred to the "homologation special," designed to provide approved equipment for World Superbike racing. Start- ing with 1996, the R is now the standard model, while the RR refers to the more track-oriented version. While Kawasaki U.S. will bring in a limited number of RR injas, "for connoisseurs" as one representative put it, the major sales thrust for 1996 will center on the inja ZX-7R. Kawasaki took the world motorcycle press to Jerez in Spain at the end of November of 1995 to sample the 1996 ZX-7R. Two dry and sunny days on the popular, smooth and fast 2.7-mile Grand Prix circuit combined with a cool and wet street-riding session to provide a good first impression of the latest "green meanie." Unfortunately, the (Top) The Kawasaki . ZX-7R comes In two color combinations. (Above) Colin Frssar at speed In Jars%, Speln. (Left) The chassis Is aluminum, with an Increase In rigidity and 1 _ Ight. _ "double R" version was on display only, so we can only provide technical information about the more costly, racier brother of the ZX-7R. At the heart of any new machine, especially one aimed squarely at the enthusiast market, is the engine. In typical hot-rod fashion, Kawasaki has gone to a shorter stroke and wider bore at 73 x 47.7mm, compared to the previous model's 71 x 47.3mm measurements. Kawasaki claims this change offers more power in the higher rpm range of the new Ninja. The ind uction side of the motor has received considerable attention, taking advantage of the larger twin ram-air ducting feeding into an improved airbox. The ports are now straighter and smoother, with the intake path between the carbs and combustion chamber also improved. The downdraft angle for the ports has been increased from 37.5 to 40 degrees, improving intake-flow charac-. teristics. The neW cylinder head has a larger included valve angle, moving from 20 to 25 degrees to speed air flow around both intake and exhaust valves. Additionally, the engine designers moved to make the engine itself more rigid, to handle the power increase. The crankshaft bearing supports were beefed up, while the crankcase has stronger ribs and increased wall thickness in the area around the output shaft. A new, closed top-deck cooling system with wet liner reduces distortion around the liner. Attention has been directed toward cylinder-head oil flow, with two large oil-return passages moving oil back to the deeper sump more quickly. The first passage is in front of and between cylinders two and three while the other is behind cylinder four, equalizing cylinder and crankcase pressures. The previous ZX-7 model had a tap- pet and rocker-arm valvetrain adjustment system, while the 1996 Ninja's are direct actuation, shim-and-bucket type. This allows for a more compact head, and offers increased reliability. Shift action is also improved with five dogs instead of six for second through fifth gears. While most of these mods were aimed at all-out performance, other changes helped to improve the midrange response. Revised valve timing settings and a new exhaust system helped broaden the ZX-7R's power delivery. Volume for the ZX-7R's exhaust system now matches that of the bigger-displacement ZX-9. Worth noting are the many powerplant differences between the Rand RR models. The R gets 38mm semi-downdraft CV type Keihins, while on the RR the size goes up to 41mm, with flat slides and completely smooth bores. The RR gets a close-ration transmission, compared to the street-oriented cog choices for the R. The crankshaft flywheel on the R has a smaller mass to make for a more free-spinning engine in ordinary use, while on the RR the mass is increased, to help improve traction. The double R also has a removable camchain sprocket, to allow for easier attrack maintenance and tuning. Goals for the chassis on the new Ninja included increased rigidity and

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