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YCC-T (Yamaha Chip Controlled Throttle)
Mechanism characteristics
FEATURES
Yamaha developed the YCC-T system empl
oy
ing the most advanced electronic control technologies.
Electronic control throttle syst
ems
have been used on automob
il
es
, but Yamaha has developed a fast-
er, more compact system specifi
ca
lly for the needs
of
a sports motorcycle. The Yamaha-developed
system has a high-speed
ca
l
cu
l
at
ing capacity that produces comput
at
ions of
ru
nning
co
nditions every
1 /1
OOOth
of
a second.
The YCC-T system is designed to respond to t
he
throttle action of the ri
der
by having the ECU instan-
taneously calc
ul
ate the ideal throttle valve opening and generate signals to operate the motor-driven
throttle
va
lves and thus
ac
tively con
tr
ol the intake air
vo
lume.
The ECU contains two CPUs
wit
h a capaci
ty
about five times that
of
co
nventional uni
ts
, making it pos·
sible for the system to respond extremely quick
ly
to the s
li
ghtest
ad
justments made by the rider. In par-
ticular, optimized
co
ntrol
of
the throttle
va
lve opening provides the
op
timum volume
of
intake air for
easy-to-use torque, even in a high-revving engine.
Aims and advantages of using YCC·T
• Increased engine power
By
shortening the air intake path, h
ig
her
engine speed is possib
le
~
Increased engine power.
• Improved
dr
iveabi
li
ty
Air intake
vo
lu
me
is controlled according
to
the operating
cond
i
ti
ons
~
Improved throttle response to
meet eng
in
e requiremen
t.
Dr
iv
in
g for
ce
is con
tr
o
ll
ed at t
he
opti
ma
l level accord
in
g
to
the
tr
ansmission
gear
position and engine
speed
~
Improved throttle control.
• Engine braking control
Due to the throttle control, optimal engine braking is made possible.
• Simplified idle speed control (ISC) mecha
ni
sm
The bypass mechanism and ISC actuator
are
e
li
m
in
at
ed
~
A simple mechanism is used to maintain
a steady idle speed.
• Reduced weight
Compared to using a sub-throttle
mec
ha
ni
sm, weight is reduced.
4
1.
Accelerator position sensor
2.
Throttle ser
vo
motor
3.
Throttle position sensor
4.
Throttle val
ves
1-9