KEY FEATURES
FUEL-INJECTED GASOLINE POWER (all KAF620 models)
Proven 617cc, 4-stroke, 90º V-twin, OHV, liquid-cooled gasoline engine features dual injector fuel injection. The switch to fuel injection
means stable power all the time, smooth response, improved power feeling, easy starting and no need to adjust engine settings to suit
climate and varying altitude conditions.
throttle valve is operated by the driver via the accelerator pedal; the
main valve is operated by a step-motor actuator which is controlled
by the ECU. The ECU uses throttle position input from the sub-valve
to determine the ideal throttle position for the main valve, ensuring
smooth inlet airflow.
* To keep the fuel injection system simple and reliable, rather than use
an atmospheric pressure sensor, the ECU calculates atmospheric
pressure using the pulse air pressure measured by the inlet pressure
sensor.
* The ECU compensates for air and engine temperature and
atmospheric pressure, ensuring sure and prompt engine starts in a
variety of conditions (including cold, high altitude, etc). Auto fast idle
when the engine is cold means being able to move out right after a
cold-engine start.
* The ECU also enforces the vehicle’s maximum speed. In Hi-gear,
the throttle is slowly closed as max vehicle speed is approached.
In Low-gear, the throttle is closed partially before fuel is cut at the
engine speed where the max vehicle speed would be exceeded.
* Kawasaki Diagnostic System (KDS) can be used to diagnose the fuel
injection system.
* Fuel pump located in the fuel tank features a built-in fuel pressure
regulator. (This system is similar to that used on motorcycles and on
Kawasaki’s fuel-injected ATVs.)
* To ensure smooth engine response, the engine features dual throttle
valves. The throttle body contains a ø34 mm upstream (sub-) throttle
valve and a ø30 mm downstream (main) throttle valve. The sub2 0 1 2 M Y M U L E 4 0 0 0 S E R I E S M O D E L I N F O R M AT I O N
* Compact and lightweight, durable and powerful, the engine is
mounted in a rubber-isolated sub-frame to ensure low vibration
levels.
* Overhead valves designed for efficient running and good fuel
economy are durable and operate quietly.
* Crankcase breathers fitted to route blow-by back to the intake pipe
for cleaner exhaust emissions.
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