HOT START YAMAHA YZ250F 2006 User Guide

2 - 20
SPEC
ÎPass the radiator breather
hose in front of the radiator, on
the left of the chassis, and then
between the frame and radiator
hose 4.
ÏFasten the sub-wire harness
and engine stop switch lead to
the CDI unit bracket at the
white-taped portion of the sub-
wire harness and with the
clamp ends facing downward.ÐLocate the clamp ends in the
arrowed range.
ÑFasten the neutral switch lead
and CDI magneto lead over the
hump of the frame.
ÒFasten the hot starter cable
and throttle cable onto the
frame. Locate the clamp ends
under the hot starter cable.
5Ð
Ð
B-B
C-C
E-E
H-H
G-G
D-D
A-A
G
4
5
1
7H
Ð B
B
0
9 F
3
Ñ
6 90F
È
9
CC
C E HH
GA
AB
E
7
3
8 3 9
Ê Ê
Ë
F
E
3
D
C
B
3
A
3
Ì Í Î Ï
1
2
3
4
5
6
3
B
0
9
A
0É
B
B 0 9
9
D
G
B
D
Ò 3
CABLE ROUTING DIAGRAM

2 - 23
SPECCABLE ROUTING DIAGRAM
1Throttle cable
2Clamp
3Hot starter cable
4Clutch cable
5Engine stop switch lead
6Cable guide
7Brake hose
8Hose guideÈFasten the engine stop switch lead to the handle-
bar.
ÉPass the clutch cable and hot starter cable
through the cable guide.
ÊPass the brake hose in front of the number plate.
ËPass the throttle cables through the cable guide.
ÌPass the clutch cable and hot starter cable
through the cable guide on the number plate.
A
B
C
A
B
C40˚± 10˚
40˚± 10˚
2
È3
2
5
4
2
3
5
6
Ë1
4
5
7
Ê
6
É
Ì
8

3 - 3
INSP
ADJ
MAINTENANCE INTERVALS
FRONT FORK OIL SEAL AND DUST
SEAL
Clean and lube Lithium base grease
PROTECTOR GUIDE
Replace
REAR SHOCK ABSORBER
(After
rain ride)
Inspect and adjust
Lube
Molybdenum disulfide
grease
Replace spring seat Every one year
Retighten
DRIVE CHAIN GUIDE AND ROLLERS
Inspect
SWINGARM
Molybdenum disulfide
grease
Inspect, lube and retighten
RELAY ARM, CONNECTING ROD
Molybdenum disulfide
grease
Inspect, lube and retighten
STEERING HEAD
Inspect free play and retighten
Clean and lube Lithium base grease
Replace bearing
TIRE, WHEELS
Inspect air pressure, wheel run-out,
tire wear and spoke looseness
Retighten sprocket bolt
Inspect bearings
Replace bearings
Lubricate Lithium base grease
THROTTLE, CONTROL CABLE Yamaha cable lube or
SAE 10W-30 motor oil
Inspect dirt and wear on
the throttle cable on the
carburetor side. Check routing and connection
Lubricate
Inspect and clean (throttle cable)
HOT STARTER, CLUTCH LEVER
Inspect free playItemAfter
break-inEvery
race
Every
third
(or
500 km)Every
fifth
(or
1,000 km)As re-
quiredRemarks

3 - 11
INSP
ADJHOT STARTER LEVER ADJUSTMENT/
AIR FILTER CLEANING
2. Apply:
Lithium soap base grease
On the throttle cable end a.
3. Install:
Throttle grip cap
Screw (throttle grip cap)
Cover (grip cap)
Cover (throttle cable cap)
T R..4 Nm (0.4 m · kg, 2.9 ft · lb)
HOT STARTER LEVER ADJUSTMENT
1. Check:
Hot starter lever free play a
Out of specification → Adjust.
2. Adjust:
Hot starter lever free play
NOTE:
After adjustment, check proper operation of
hot starter.
AIR FILTER CLEANING
NOTE:
Proper air filter maintenance is the biggest key
to preventing premature engine wear and
damage.
CAUTION:
Never run the engine without the air filter
element in place; this would allow dirt and
dust to enter the engine and cause rapid
wear and possible engine damage.
1. Remove:
Seat
Fitting bolt 1
Washer 2
Air filter element 3
Air filter guide 4
Hot starter lever free play
a:
3 ~ 6 mm (0.12 ~ 0.24 in)
Hot starter lever free play adjustment
steps:
Loosen the locknut 1.
Turn the adjuster 2 until free play a is
within the specified limits.
Tighten the locknut.

3 - 44
INSP
ADJ
LUBRICATION
LUBRICATION
To ensure smooth operation of all compo-
nents, lubricate your machine during setup,
after break-in, and after every race.
1All control cable
2Clutch lever pivot
3Shift pedal pivot
4Footrest pivot
5Throttle-to-handlebar contact
6Drive chain
7Tube guide cable winding portion
8Throttle cable end
9Clutch cable end
0Hot starter cable end
ÈUse Yamaha cable lube or equivalent on these
areas.
ÉUse SAE 10W-30 motor oil or suitable chain
lubricants.
ÊLubricate the following areas with high quality,
lightweight lithium-soap base grease.
CAUTION:
Wipe off any excess grease, and avoid get-
ting grease on the brake discs.
AAA
AAB
CC

4 - 2
ENG
REMOVAL POINTS
Side cover
1. Remove:
Bolt (side cover)
Left side cover 1
Right side cover 2
NOTE:
Draw the side cover downward to remove it
because its claws a are inserted in the air fil-
ter case.
Number plate
1. Remove:
Bolt (number plate)
Number plate 1
NOTE:
The projection a is inserted into the band of
the number plate. Pull the band off the pro-
jection before removal.
Remove the hot starter cable 2 and clutch
cable 3 from the cable guide b on the num-
ber plate.
The projection c on the lower bracket is
inserted into the number plate. Remove the
number plate by pulling it off the projection.
ASSEMBLY AND INSTALLATION
Air scoop
1. Install:
Air scoop 1
Bolt (air scoop)
NOTE:
Put the portion a of the flap of the air filter
case on the inside of the air scoop.
T R..7 Nm (0.7 m · kg, 5.1 ft · lb)
SEAT, FUEL TANK AND SIDE COVERS

4 - 9
ENGCARBURETOR
CARBURETOR
3
97
8
4
4
2
T R..3 Nm (0.3 m • kg, 2.2 ft • Ib)
T R..3 Nm (0.3 m • kg, 2.2 ft • Ib)
T R..4 Nm (0.4 m •
kg, 2.9 ft • Ib)
T R..4 Nm (0.4 m •
kg, 2.9 ft • Ib)
T R..2 Nm (0.2 m •
kg, 1.4 ft • Ib)
T R..11 Nm (1.1 m •
kg, 8.0 ft • Ib)
5 1
6
6
Extent of removal:
1 Carburetor removal
Extent of removal Order Part name Q’ty Remarks
CARBURETOR REMOVAL
Preparation for removal Seat and fuel tank Refer to “SEAT, FUEL TANK AND SIDE
COVERS” section.
1Clamp 1
2 Throttle position sensor lead cou-
pler1
3 Throttle cable cover 1
4 Throttle cable 2
5 Clamp (air filter joint) 1 Loosen the screw (air filter joint).
6 Clamp (carburetor joint) 2 Loosen the screws (carburetor joint).
7 Hot starter plunger 1
8 Carburetor assembly 1
9 Carburetor joint 1
1

4 - 15
ENG
Starter plunger
1. Inspect:
Cold starter plunger 1
Hot starter plunger 2
Wear/damage → Replace.
Accelerator pump
1. Inspect:
Diaphragm (accelerator pump) 1
Spring (accelerator pump) 2
Accelerator pump cover 3
O-ring 4
Push rod 5
Tears (diaphragm)/damage → Replace.
Dirt → Clean.
2. Inspect:
Throttle shaft 1
Spring 2
Lever 1 3
Spring 1 4
Lever 2 5
Spring 2 6
Dirt → Clean.
12
3456
ASSEMBLY AND INSTALLATION
Carburetor
1. Install:
Cold starter plunger 1
2. Install:
Pilot air jet 1
1
CARBURETOR

4 - 21
ENG
3. Install:
Hot starter plunger 1
1T R..2 Nm (0.2 m · kg, 1.4 ft · lb)
4. Tighten:
Bolt (air filter joint) 1
Bolt (carburetor joint) 2
2
1
T R..3 Nm (0.3 m · kg, 2.2 ft · lb)
T R..3 Nm (0.3 m · kg, 2.2 ft · lb)
5. Install:
Throttle cable (pull) 1
Throttle cable (return) 2
6. Adjust:
Throttle grip free play
Refer to “THROTTLE CABLE ADJUST-
MENT” section in the CHAPTER 3.2
1
T R..4 Nm (0.4 m · kg, 2.9 ft · lb)
T R..11 Nm (1.1 m · kg, 8.0 ft · lb)
7. Install:
Throttle cable cover 1
Bolt (throttle cable cover) 2
2 1
T R..4 Nm (0.4 m · kg, 2.9 ft · lb)
8. Install:
Throttle position sensor lead coupler 1
Clamp 2
Refer to “CABLE ROUTING DIAGRAM”
section in the CHAPTER 2.
1
2
CARBURETOR

5 - 43
CHASHANDLEBAR
EC5B0000
HANDLEBAR
Extent of removal:
1 Handlebar removal
Extent of removal Order Part name Q’ty Remarks
Preparation for removal
HANDLEBAR REMOVAL
Number plate Remove the band only.
1 Hot starter cable 1 Disconnect at the lever side.
2 Hot starter lever holder 1
3 Clutch cable 1 Disconnect at the lever side.
4 Clutch lever holder 1
5 Engine stop switch 1
6 Brake master cylinder 1 Refer to “REMOVAL POINTS”.
7 Throttle cable cap 1
8 Throttle cable #1 (pulled) 1 Disconnect at the throttle side.
9 Throttle cable #2 (pushed) 1 Disconnect at the throttle side.
10 Right grip 1 Refer to “REMOVAL POINTS”.
11 Tube guide 1
12 Collar 1
13 Left grip 1 Refer to “REMOVAL POINTS”.
14 Handlebar upper holder 2
15 Handlebar 1
16 Handlebar lower holder 2
1