In a somewhat surprise move, Kawasaki has chosen to once again disregard conventional displacement categories, except this time with the debut of the new 2013 ZX-6R and its smaller Ninja 300 brother. The new ZX-6R’s engine grows to a 636cc displacement, which harkens back to 2003-2006 ZX-6R edition that had the same size powerplant, while the venerable Ninja 250’s engine has been enlarged to 296cc from its previous 249cc iteration. Both bikes feature numerous chassis and styling upgrades in addition to the larger and more powerful engines. Kawasaki has been on a roll lately with regards to sportbike market share in the U.S. (it has occupied the number one slot the past few years), and it’s clear the company is looking to maintain that growth with the introduction of the latest Ninjas.
The 2013 Kawasaki ZX-6R moves...
The 2013 Kawasaki ZX-6R moves back up to 636cc displacement, along with a host of other updates including traction control.
The ZX-6R’s displacement growth was achieved via a 2.6mm stroke increase to 45.1mm, while bore remains the same at 67mm. The longer stroke not only permitted a decrease in compression ratio from the previous sky-high 13.3:1 to 12.9:1, the cylinder head’s intake and exhaust ports were reshaped and the chromoly steel cams’ lift/timing revised to take advantage of the engine configuration change to provide increased power across the rev range.
New pistons feature revised crown and moly coating on the skirts, while the new piston pins are now straight in design (instead of tapered) to help maintain high-rpm reliability. The connecting rods are shorter and stronger, with thicker stems and larger small ends to handle the increased torque from the long-stroke engine.
Up top, the larger airbox boasts 12.5 percent more volume, and the previous “siamesed” intake velocity stacks have been jettisoned in favor of longer individual funnels for improved low-midrange power. Down inside the throttle bodies, new injectors provide an ultra-fine sub-60-micron fuel droplet spray for improved combustion while also possessing increased fuel flow capability for the larger engine.
The power from the 2013 Kawasaki ZX-6R's larger engine is delivered through a new F.C.C. clutch (a Japanese OEM clutch company that has developed many racing clutch setups and sponsored some Grand Prix teams) with power-assist and slipper functions. Two cams—one for power and the other for back-torque—work in tandem to provide multiple benefits. The power-assist cam works like a servo to pull the clutch plates and basket/hub together under power, permitting the number of clutch springs and tension to be reduced (resulting in a claimed 20 percent reduction in clutch lever effort) while also boosting its maximum torque load capacity. Under deceleration, the back-torque cam allows the clutch plates to slip, while a new spring plate assembly offers smoother engagement, and a lighter aluminum (instead of steel) clutch hub drops 600 grams from the unit. The same cassette transmission is now equipped with a shorter first gear, stronger alloys, and revised gear thicknesses to work with the engine’s increased power.
The 2013 ZX-6R is also available...
The 2013 ZX-6R is also available in all black and this white version.
Like the ZX-10R and ZX-14R, the new 2013 ZX-6R is equipped with a version of Kawasaki’s KTRC traction control system. Full or Low power mode options (Low begins to limit power as rpm rises into the midrange, up to 80 percent of maximum power, along with softer throttle response) are selectable, with a three-level TC that is claimed to have more advanced programming than the ZX-10R’s S-KTRC unit.
An all-new Showa Big Piston/Separate Function Fork (BP/SFF) features a unique setup that is claimed to save 220 grams. The fork has springs in both sides, but only the left side is preload adjustable. The adjustable compression/rebound damping is handled by the right fork leg’s Big Piston setup. Out back, a 25mm-longer spring (softer rate) is paired with a linkage with a higher leverage ratio for improved compliance. Braking is handled by new monobloc radial-mount Nissin calipers that are 90 grams lighter biting on 310mm petal-style rotors, with a new lighter rear caliper clamping on the same 220mm rotor. The ZX-6R is also available in an ABS version utilizing the same KIBS (Kawasaki Intelligent Braking System) setup as the ZX-10R ABS model (the ABS model is claimed to be just 4.4 pounds heavier than the 423.4-pound standard ZX-6R). The twin-spar aluminum frame has been subtly altered to work with the more powerful engine, and has a tighter 23.5-degree/4.0 trail steering geometry than the previous model’s 24.0-degree/4.1-inch configuration.
The standard ZX-6R will retail for $11,699, while the ABS version will sell for $12,699.
The new 2013 Ninja 300 boasts...
The new 2013 Ninja 300 boasts a whole range of upgrades to accompany its larger engine.
The new Ninja 300’s parallel twin powerplant gained its extra 47cc of displacement with a whopping 7.8mm stroke increase, with the bore and stroke configuration now at 62.0 x 49.0mm. The engine is much more than just a stroked Ninja 250 mill, however; Kawasaki claims that nearly 50 percent of the engine’s parts were upgraded. The cylinder head features 1mm-larger intake valves (now 23.6mm) along with reshaped intake ports (1mm wider at the throttle bodies, 0.5mm wider at the valves); new lighter pistons force a lower 10.6:1 compression ratio (from the previous 11.6:1 of the 250) to allow the use of regular 87 octane gasoline. Thicker crank webs, stronger alloy main bearings, new crankcases with improved oil passages and larger 2.4-liter oil pan, and shorter connecting rods help handle the increased power; new rubber engine mounts ensure smooth, vibe-free cruising.
Up top, digital fuel injection has finally made its way to the smallest Ninja, with the 300 utilizing a Keihin system with dual 32mm throttle bodies to feed the parallel twin. Down below, the 296cc engine exhales through a new 2-into-1 exhaust system. The six-speed transmission features a new roller shift drum and stronger-construction gears, and utilizes an F.C.C. Assist Clutch setup similar to the ZX-6R.
The 2013 ZX-14R is basically...
The 2013 ZX-14R is basically unchanged, but will be available in this tasteful black/green trim paint scheme.
The frame has been redesigned with steel tubing that is claimed to be 150 percent more rigid than the Ninja 250R’s, with revised tube shapes and additional gusseting contributing to the 300’s improved handling. Interestingly, Kawasaki says that the suspension rates were also revamped to compliment the stiffer chassis, but lists softer spring rates for “a more comfortable ride on city streets without compromising sport handling characteristics.” The Ninja 300’s rear wheel is 0.5 inches wider, allowing the fitment of a larger 140-size rear tire.
New bodywork not only looks sharper, but also provides improved heat management by directing hot exhaust airflow from the radiator down below the engine instead of out the sides where it would hit the rider’s legs. And the Ninja 250R’s antiquated analog tachometer/speedometer dashboard has finally been modernized, with a nicer-looking analog tach accompanied by a LCD panel for the digital speedometer and important engine functions. All told, the new Ninja 300 is claimed to be only 4.4 pounds heavier than the Ninja 250R at 379.3 pounds, although the Ninja 300 ABS model gains another 4.4 pounds on the standard model.
The 2013 Ninja 300 will retail for $4799, while a Limited Edition version with special paint/graphics will sell for $4999, while the LE ABS version will sell for $5499.