Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles
Issue link: https://magazine.cyclenews.com/i/126792
K wasaki LTD 450 Ninja 600 frame has removable lower downtube sections to ease engine removal and replacement; frame tubes are rectangular cross-section steel. Belt-drive LTO 450 has a gear-driven engine counter-balancer and OOHC four-valves-per-cylinder engine; it's water-cooled. Kawasaki l TD450 Specifications Engine Type jacket. Coolant is routed through the'cylinder waterjackets and then into the cylinder head, running from the head LO the aluminum radiator; a compact electric [an mounted behind the radiator is controlled by a thermostat. Despite water·cooling, a dry 600 engine weighs 2.2 pounds less than a dry GPz550 engine. The GPz600R's 32mm Keihin CV carburetors have the same type of semi-flat sl ides (small-diameter round centers with Hat side extensions) as the Keihins found on the GPz900R. The [our-into-two exhaust system's header pipes aren't double-wall for their en tire length. Instead, the extra wall only extends 1.6 inches from the exhaust pon; that makes the system lighter. The GPz600R's frame is made o[ rectangular cross-section steel tubing, with widely-spaced backbone tubes running around the cylinder head and carbs to the swingarm pivot. Two downtubes are welded LO the steering stem and reach LO a point just above the front engine mounts; there's a cross- brace tu be between the downtubes there; two removable tubes boIL between the down tubes and the swingarm pivot plate, making engine installation and removal possible. The seat-and-tailsection-supporting rear section of the frame is made of smaller rectangular tubing and is welded to the main frame section. A single rear shock witl) adjustable rebound damping and air assist is mounted at its LOp to the upper frame behind the backbone tubes; the bottom o[ the shock connects LO the frame - below the s.wingarm - and the extruded aluminum alloy swingarm itself through a pivoting aluminum alloy linkage. The swingarm pivots on needle roller bearings. Wheelbase is 56.3 inches, rake 27°. The 37mm-sLanchion·tube front forks turn on tapered roller bearings and are equipped with Kawasaki AVOS (Automatic Variable Damping System) anti-dive. The AVOS is adjusta· ble [or anti-dive e[[ect, with three different sellings, and is activated by the front brakes; compression damping increases - and thus the rate o[ fork compression decreases - according LO initial fork travel and initial peed of compression. The system includes a blow-o[f valve LO allow the forks LO react to bumps encountered during hard braking. Water-cooled DOHC parallel twin Bore x Stroke 72.5x55mm Displacement 454cc Compresssion Ratio 10.7:1 Carburetion (2) 34mm Keihin CV Horsepower 49.3 bhp @ 9500 rpm Torque 30.4 lb.-ft. @ 8000 rpm Valves Per Cylinder 4 Intake Valve Timing 35°-55° Exhaust Valve Timing 60°-30° (measuring pt.) Omm Ig.nition Transistorized electronic lubrication Wet sump Redline : 10000 rpm rpm @60mph 5300 rpm Gear Ratios Primary 2.952 Final 2.720 6th 0.851 5th 0.961 4th 1.125 3rd 1.380 There's a forged aluminum fork brace with a wing aimed LO direct cooling air attne radiaLOr; Kawasaki says the airstream off the wing decreases coolant temperature about 48° F. The front fender is Hared to wrap around the upper pan of the fork sliders, improving aerodynamics. The GPz6OOR's front brake discs are larger than the GPz550's, measuring 10.6 inches vs. the 550's 1O.2-inch discs, and Kawasaki says new sintered metal pads have a 10% higher coe[[icient o[ friction and a 20% longer life, which, i[ true, is a prelly good trick. The rear brake measures 9.8 inches. Both cast aluminum alloy wheels are 16-inch, a 2.5-16 [rontanda 3.0-16 rear, carrying I 10/90 and 130/90 tires respectively. Wrapped around all this is a frame-mounted [airing, the upper section made of ABS plastic and the bollom section made o[ PBT plastic which Kawasaki says is more abrasion resistant, an important consid- 2nd 1.777 1st 2.571 Calculated Speed in Gears At Redline 6th 114 mph 5th 101 mph 4th 86 mph 3rd 70 mph 2nd 55 mph 1st 38 mph Rake 31.5° Trail 5.47 in. Front Suspension Type Telescopic forks Front Wheel Travel 6.3 in. Rear Suspension Type Dualshock swingarm Rear Wheel Travel 4.3 in. Front Brakes Disc Rear'Brakes 7.1x1.6-in. drum Front Tire 100/90-19 RearTire 140/90-15 Dry Weight 399 Ibs. 58.5 in. Wheelbase Fuel Capacity 2.9 gal. Ground Clearance 5.1 in. Seat Height. . . . . . . . . . .. 29 in. eration [or hard-core [airing draggers. What looks LO be aluminum braces wrapping around the fairing at the junction o[ the upper and lower pieces are actually strips of silver PBT plastic. There's an optional cover [or the passenger seat [or solo riding, and a storage compartment is hidden underneath the seat. The handlebars are forged aluminum and non-adjustable, and the usual array of Kawasaki instruments - 13,000 rpm tach, 160mph speedometer, warning aDd indicator lights and water temperature gauge - are mounted inside the frame-mounted fairing and don't pivot with the handlebars. In the U.S. and Canada the GPz600R will carry the legend "Ninja 600R" on the [airing; the photos shown here are o[ a European model. The U.S. and Canadian models also will come with shoner rear [enders. GPz600Rs should be in dealer showrooms by December. Retail price hasn't been announced. • .., 35