Yamaha 2008 WR450F, Owner'S Service Manual

Page: 103 / 220

5-9
CARBURETOR
9. Install:
•
Push rod "1"
While holding down the lever 1 "2", in-
sert the push rod farthest into the car-
buretor.
10. Install:
•
Starter jet "1"
• Pilot jet "2"
•
Spacer "3"
• Needle jet "4"
•
Main jet "5"
11. Install:
•
Needle valve "1"
• Float "2"
•
Float pin "3"
•
After installing the needle valve to
the float, install them to the carbure-
tor.
• Check the float for smooth move-
ment.
12. Install:
• O-ring
•
Leak jet "1"
• Float chamber "2"
•
Bolt (float chamber) "3"
• Cable holder (throttle stop screw
cable) "4"
• Hose holder (carburetor breather
hose) "5"
13. Install:
•
Diaphragm (air cut valve) "1"
• Spring (air cut valve) "2"
•
O-ring "3"
• Air cut valve cover "4"
•
Holder (cylinder head breather
hose) "5"
•
Screw (air cut valve cover) "6"
14. Install:
•
Diaphragm (accelerator pump)
"1"
•
Spring "2"
• O-ring "3"
•
Accelerator pump cover "4"
• Hose holder (drain hose) "5"
•
Screw (accelerator pump cover)
"6"
Install the diaphragm (accelerator
pump) with its mark "a" facing the
spring.
15. Install:
• Jet needle "1"
•
Collar "2"
• Spring "3"
•
Needle holder "4"
• Throttle valve plate "5"
To throttle valve "6".
16. Install:
• Throttle valve assembly "1"
• Screw (throttle shaft) "2"
Install the valve lever rollers "3" into
the slits "a" of the throttle valve.
17. Install:
•
O-ring "1"
• Valve lever housing cover "2"
•
Bolt (valve lever housing cover)
"3"
18. Install:
• Carburetor breather hose "1"
Refer to "CABLE ROUTING DIA-
GRAM" section in the CHAPTER
2.
Install the carburetor breather hoses
to the carburetor so that the hoses do
not bend near where they are in-
stalled.
ADJUSTING THE ACCELERATOR
PUMP TIMING
Adjustment steps:
In order for the throttle valve height
"a" to achieve the specified value,
tuck under the throttle valve plate "1"
the rod "2" etc. with the same outer di-
ameter as the specified value.
Throttle valve height:
3.1 mm (0.122 in)