Yamaha YZF-R1P 2001-2003, Service Manual

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GEN
INFO
FEATURES
Fuel injector
Upon receiving injection signals from the ECU, the fuel injector injects fuel. In the normal state, the
core is pressed downward by the force of the spring, as illustrated. The plunger that is integrated
with the bottom of the core keeps the fuel passage closed.
When the current flows to the coil in accordance with the signal from the ECU, the core is drawn
upward, allowing the flange that is integrated with the plunger to move to the spacer. Since the dis-
tance of the movement of the needle is thus kept constant, the opening area of the fuel passage
also becomes constant. Because the pressure difference of the fuel to the intake manifold pressure
is kept constant by the pressure regulator, the fuel volume varies in proportion to the length of time
the coil is energized. The injector that has been recently adopted has a four-hole type injection ori-
fice that enhances the atomization of fuel and improves combustion efficiency.
1
Fuel
2
Coil
3
Core
4
Plunger
5
Inject
6
Flange