Checking The Throttle Body Joints; Checking The Canister - Yamaha MTN850-A 2017 Service Manual

dard. Otherwise, the engine may run roughly
at idle and the throttle bodies may not oper-
ate properly.
TIP
• Turn the bypass air screw using the carburetor
angle driver.
• After each step, rev the engine two or three
times, each time for less than a second, and
check the synchronization again.
• If a bypass air screw was removed, turn the
screw in fully and be sure to synchronize the
throttle bodies.
• If the throttle body synchronization can not be
adjusted using the bypass air screw, clean or
replace the throttle bodies.
• The difference in vacuum pressure between
the throttle bodies should not exceed 1.33 kPa
(10 mmHg).
Carburetor angle driver 2
90890-03173
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
2. Stop the engine and remove the measuring
equipment.
3. Install:
• Caps
4. Install:
• Air filter case
Refer to "GENERAL CHASSIS (2)" on page
4-7.
• Fuel tank
Refer to "FUEL TANK" on page 7-1.
• Fuel tank cover
Refer to "GENERAL CHASSIS (1)" on page
4-1.
• Rider seat
Refer to "GENERAL CHASSIS (1)" on page
4-1.
• Air scoop
Refer to "GENERAL CHASSIS (1)" on page
4-1.
PERIODIC MAINTENANCE
5. Adjust:
• Throttle grip free play
Refer to "CHECKING THE THROTTLE
GRIP" on page 3-29.
EAS30798

CHECKING THE THROTTLE BODY JOINTS

1. Remove:
• Throttle bodies
Refer to "THROTTLE BODIES" on page 7-5.
2. Check:
• Throttle body joints "1"
Cracks/damage  Replace.
3. Install:
• Throttle bodies
Refer to "THROTTLE BODIES" on page 7-5.
1
EAS31922

CHECKING THE CANISTER

1. Remove:
• Air scoop
Refer to "GENERAL CHASSIS (1)" on page
4-1.
• Rider seat
Refer to "GENERAL CHASSIS (1)" on page
4-1.
• Fuel tank cover
Refer to "GENERAL CHASSIS (1)" on page
4-1.
• Fuel tank
Refer to "FUEL TANK" on page 7-1.
2. Check:
• Canister
• Canister purge hose
• Fuel tank breather hose
• Canister breather hose
Cracks/damage  Replace.
3. Install:
• Fuel tank
Refer to "FUEL TANK" on page 7-1.
3-10
Throttle grip free play
3.0–5.0 mm (0.12–0.20 in)
1