Yamaha WR250F(N), Owner'S Service Manual

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ENG
CARBURETOR
2. Inspect:
●
Main jet 1
●
Pilot jet 2
●
Needle jet 3
●
Starter jet 4
●
Main air jet 5
●
Pilot air jet 6
●
Leak jet 7
Damage
→
Replace.
Contamination
→
Clean.
NOTE:
●
Use a petroleum based solvent for cleaning.
Blow out all passages and jets with com-
pressed air.
●
Never use a wire.
Needle valve
1. Inspect:
●
Needle valve 1
●
Valve seat 2
Grooved wear
a
→
Replace.
Dust
b
and
c
→
Clean.
NOTE:
Replace the needle valve and valve seat as a
set.
EC464301
Throttle valve
1. Check:
●
Free movement
Stick
→
Repair or replace.
NOTE:
Insert the throttle valve 1 into the carburetor
body, and check for free movement.
EC464401
Jet needle
1. Inspect:
●
Jet needle 1
Bends/wear
→
Replace.
●
Clip groove
Free play exists/wear
→
Replace.
●
Clip position
* For EUROPE
** For CDN, ZA, AUS and NZ
Standard clip position:
No.3 Groove
*
,
** No.4 Groove