Yamaha 2009 YZF-R1 (Y), Service Manual, Page: 377 / 546

THROTTLE BODIES
7-16
TIP
If the protector “a” is scratched or damaged,
replace the throttle bodies as a set.
2. Clean:
• Throttle bodies
ECA14B1047
Observe the following precautions; other-
wise, the throttle bodies may not operate
properly.
• Do not open the throttle valves quickly.
• Do not subject the throttle bodies to
excessive force.
• Clean the throttle bodies with a cloth
which petroleum-based solvent is applied
on.
• Do not use any caustic carburetor clean-
ing solution.
• Do not apply cleaning solvent directly to
any plastic parts, sensors, or seals.
• Do not directly push the throttle valves to
open them.
• Do not touch the bypass air screw “a”
with a white paint mark; otherwise, the
throttle body synchronization will be
affected.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Place the throttle bodies on a flat surface
with the air filter case side facing up.
b. Install the caps (895-14169-00) onto the
hose fittings “a”.
c. Push the lever in the direction shown in the
illustration to hold the throttle valves in the
open position.
WARNING
EWA14B1022
When cleaning the throttle bodies, be care-
ful not to injure yourself on the throttle
valves or other components of the throttle
bodies.
ECA14B1028
Do not open the throttle valves by supply-
ing electrical power to the throttle bodies.
d. Apply a petroleum-based solvent to the
throttle valves and the inside of the throttle
bodies to remove any carbon deposits.
TIP
• Do not allow any petroleum-based solvent to
enter the opening for the injectors.
• Do not apply any petroleum-based solvent to
the portions of the throttle valve shafts
between the throttle bodies.
e. Remove the carbon deposits from the
inside of each throttle body in a downward
direction, from the air filter case side of the
throttle body to the engine side.