Kawasaki Z900RS Café

ENGINE

The engine is based on that of the Z900, but re-tuned to create an engine character that’s completely different. While the Z900 engine has a sharp, quick-revving nature that encourages high-rpm operation, the Z900RS was tuned for low-mid range power, delivering strong torque that facilitates control for riders of all skill levels. Below 7,000 rpm the engine actually pulls stronger than the Z900.

- Cam profiles with shorter intake (270˚ to 248˚) and exhaust (256˚ to 244˚) duration focus engine performance in the low-mid rpm range. Strong and smooth response gives the engine a very manageable character.
- Compression ratio is reduced from the Z900’s 11.8:1 to 10:8 to complement the shorter duration valve openings.
- Crankshaft with an approximately 12 percent heavier flywheel mass than the Z900 contributes to the Z900RS’s smooth character.
- Die-cast cylinder block is rigid while its open deck design helps save weight.
- Connecting passageways between the cylinders help reduce pumping loss, improving high-rpm performance.
- The pistons are formed using the same unique casting process that is used for making those found in the Ninja H2™/H2™R. The process creates hollow areas to achieve idealized thickness for reduced weight without sacrificing strength.
- Downdraft intake design provides the fuel mixture with the straightest, shortest path to the combustion chamber to contribute to performance.
- Stylish fins built into the cylinder head help create an image of an air-cooled engine to further invoke the original Z1 heritage.
- Die-cast aluminum engine covers are also inspired by the Z1, with the clutch cover and many other parts featuring Z1 motifs.

Digital Fuel Injection(KP)

- 36mm throttle bodies are used for their ideal mid-range response.
- Sub-throttle valves, located behind the main throttle valves, are controlled by the ECU so the EFI system has smooth, sensitive throttle response.

Exhaust System

- Extensive sound research used to craft the ideal exhaust note that emphasizes the engine’s sound at initial start-up, during idle, and while riding a lower speeds where the rider is best able to enjoy the exhaust’s deep rumble.
- Dual-wall header pipes give the exhaust a more powerful appearance while making them resistant to heat discoloration over time.
- 4-into-1 exhaust with short megaphone muffler contributes to the retro image while enhancing the exhaust note.
- Exhaust system is formed from high-quality stainless steel and triple buffed to a lustrous shine.
- Pre-chamber helps centralize mass, reduces muffler size and contributes to the exhaust note.

Assist and Slipper Clutch(KP)

- Using the rotational forces fo the clutch hub and pressure plate, the clutch is forced together during acceleration (assist function) so that fewer and lighter clutch springs can be used for a lighter feel at the lever. During high back torque, such as when too low of gear is selected during downshifting, the slipper function allows some clutch slippage to help prevent rear wheel hop and stalling due to engine lock-up.
- Judder spring component helps prevent judder when the clutch is disengaged.

Transmission

- Gearing is optimized for the Z900RS’ engine character.
- Compared to the Z900, a shorter first gear combined with the engine’s strong low-end torque facilitates moving off from a stop, while a longer sixth gear allows the engine to run a lower rpm when cruising at highway speeds for increased ride comfort.

Kawasaki Traction Control System (KTRC)(KP) (2-MODE)

- 2-mode system offers enhanced sport riding performance and rider assurance by facilitating smooth riding on slippery surfaces. The operator can also choose to turn the system off.
- Mode 1 features highly-sophisticated programming that allows a degree of wheel slip to maximize acceleration. The system looks at a number of parameters to get an accurate real-time picture of what is going on: front and rear wheel speed (slippage) and various engine, machine and rider input parameters are monitored. Complex analysis predicts when traction conditions are about to become unfavorable and the system acts before wheel slippage exceeds the range for optimal traction.
- Mode 2 has higher sensitivity and controls ignition timing, fuel and air for ultra-smooth operation.
- The system uses minimal hardware but complex software. Apart from the engine ECU, the system relies on only front and rear wheel speed sensors so that it is light weight.

CHASSIS

Trellis Frame

- Using Kawasaki’s advanced analysis technology, the trellis frame was designed to accommodate the slim teardrop fuel tank and offer the retro-style handling optimal for enjoyable riding at a more measured pace.
- Compared to the aggressive, forward-leaning stance of the Z900, the Z900RS has a neutral, or even, stance achieved by raising the front and lowering the rear. Suspension settings were chosen to achieve a high level of comfort for more relaxed riding.
- The upper-triple clamp increases the steering offset by 6 mm (from 28mm to 34mm over the Z900), which reduces trail to help quicken the steering and contribute to light handling.
- Frame components follow the ideal pipe line so that the lines of the frame are as straight as possible. When bends were necessary their angles were as small as possible, resulting in a design that disperses stress extremely well.
- Five-point, rigidly-mounted engine is a stressed member, which contributes to weight savings.
- Twin-tube rear frame section contributes to the low seat height and easy reach to the ground while minimizing vibration transferred though the seat.

Inverted Front Fork

- 41mm inverted front fork contributes to excellent ride comfort and sporty riding potential.
- 10-way compression and 12-way rebound damping adjustment allows fine-tuning for rider preference and riding style.

Horizontal Back-link Rear Suspension(KP)

- Fitted with Kawasaki’s modern suspension technology for a higher level of sporty riding potential and matches the front fork’s level of ride comfort and sporty performance.
- The linkage is placed atop the swingarm for better mass centralization and to place the lay-down shock absorber further away from the exhaust so that its operation will not be affected by exhaust heat. The shock has adjustable preload and rebound damping.
- Extruded aluminum swingarm is lightweight and contributes to the light handling.

Brakes

- Dual 300mm front discs are clamped by dual opposed piston monobloc calipers that provide a firm feel from the initial touch for superb brake performance.
- The machined Monobloc calipers have an alumite coating and laser-etched Kawasaki logo to add to the high-quality sporty appearance.
- Radial pump master cylinder also contributes to the superb control and feel offered by the calipers.
- Sintered brake pads contribute to the superb feel.

Anti-Lock Braking System (ABS)(KP)

- ABS helps provide an added degree of reassuring braking performance.

Wheels & Tires

- Cast wheels feature flat spokes designed to look like classic wire-spoked wheels. Designed using Kawasaki’s advanced analysis technology, the wheels offer a balance of light weight and stylish looks, contributing to both handling and the retro Z1 design.
- On some colors, machining on the spokes and rim edge contributes to the bike’s high-quality image.
- Dunlop GPR-300 tires contribute to retro-style looks.

Z1 RETR0 STYLING

Distinctive Z Styling

With a seamless blend of Z1-inspired styling elements and modern craftsmanship – from the iconic teardrop fuel tank to the innovative oval LED taillight – the Z900RS offers timeless good looks with an exquisite attention to detail and superb fit-and-finish. From the top-quality paint on the fuel tank to the high-grade coating for the bolts, attention to the smallest detail, carefully considered wire routing, and a clean fit-and- finish contribute to the Z900RS’ high-quality appearance.

- The centerpiece teardrop fuel tank is reminiscent of the Z1 and the frame was designed to accommodate the tank’s ideal position and slim shape.
- Complementing the rich paint used on the tank, immersion graphics on the candytone brown model result in a design that does not leave a raised surface, resulting in a high- quality finish.
- The 4.5-gallon fuel tank actually extends down behind the side covers, a layout that maintains the slim design of the tank while offering greater tank volume for extended cruising range.
- Stylish fuel tank cap complements the elegant lines of the tank.
- Side covers were designed to flow naturally from the tank. Emblems on the side covers contribute to the retro styling.
- Knee grip covers, located forward of the side covers, are pressed aluminum pieces with a clear alumite coating for an attractive, long-lasting finish.
- A blend of retro and modern designs, the large-diameter LED headlamp casts a bright, white light for great night- time visibility. Position lamps in the high-beam chambers ensure the whole lamp appears lit, like a retro-style bulb headlamp. Convex lens and chromed headlamp ring add to the retro design.
- Round mirrors are styled after those of the Z1, contributing to the retro looks while ensuring good rearward visibility.
- Three-piece front fender uses die-cast aluminium fender supports, adding a high-quality touch and enhancing the retro image. The supports are extremely thin, measuring only 1.7mm thick, to keep weight down.
- Stylish two-tone seat uses different materials for the top and sides to create a high-quality design. Double-stitching adds to the high-quality image.
- Flowing design of the rear cowl was inspired by the duck- bill tail cowl of the Z1.
- The oval design of the LED taillight is another homage to the Z1. Unlike standard LED taillights that appear as a collection of dots, the surface-emitting LED taillight lights up as a solid surface, creating a design that is both retro and modern.
- Convenient luggage hooks on the tail cowl and rear flap were designed to protrude to help prevent tie- down cords from rubbing on the elegant bodywork.
- Dual-Dial Instrumentation with Multi-Function LCD.
- Analogue-style speedometer and tachometer dials are complemented by a multi-functional LCD screen, balancing retro-style looks with modern functionality.
- Bullet-shaped dial cases provide the retro look, while a spindle finish on the dial faces adds to a more modern, high-quality design.
- LCD screen features a negative display (white letters on a black background), adding to the instrument cluster’s sporty, modern appearance.
- Gear position indicator increases shifting precision and confidence.
- In addition to the gear position indicator, display functions include: odometer, dual trip meters, fuel gauge, remaining range, current and average fuel consumption, coolant temperature, external temperature, clock and the Economical Riding Indicator. The Economical Riding Indicator appears on the LCD screen to indicate favorable fuel consumption to assist riders to maximize fuel efficiency.