2001 YAMAHA YZ426F start stop button

GEN
INFO

1 - 1
DESCRIPTION
EC100000
GENERAL INFORMATION
EC110000
DESCRIPTION
1
Clutch lever
2
Decompression lever
3
Front brake lever
4
Throttle grip
5
Radiator cap
6
Fuel tank cap
7
Oil filler plug/dipstick
8
“ENGINE STOP” button
9
Kick starter
0
Fuel tank
A
Radiator
B
Coolant drain bolt
C
Rear brake pedal
D
Valve joint
E
Fuel cock
F
Cold starter knob
G
Hot starter knob (red)
H
Drive chain
I
Air cleaner
J
Shift pedal
K
Front fork
NOTE:

l
The machine you have purchased may differ
slightly from those shown in the following.
l
Designs and specifications are subject to
change without notice.
1

1 - 10
GEN
INFO
CONTROL FUNCTIONS
EC150000
CONTROL FUNCTIONS
EC151000
“ENGINE STOP” BUTTON
The “ENGINE STOP” button 1 is located on
the left handlebar. Continue pushing the
“ENGINE STOP” button till the engine comes
to a stop.
EC152000
CLUTCH LEVER
The clutch lever 1 is located on the left han-
dlebar; it disengages or engages the clutch.
Pull the clutch lever to the handlebar to disen-
gage the clutch, and release the lever to
engage the clutch. The lever should be pulled
rapidly and released slowly for smooth starts.
EC153000
SHIFT PEDAL
The gear ratios of the constant-mesh 5 speed
transmission are ideally spaced. The gears
can be shifted by using the shift pedal 1 on
the left side of the engine.
EC154000
KICK STARTER
Rotate the kick starter 1 away from the
engine. Push the starter down lightly with your
foot until the gears engage, then kick smoothly
and forcefully to start the engine. This model
has a primary kick starter so the engine can be
started in any gear if the clutch is disengaged.
In normal practices, however, shift to neutral
before starting.
1

1 - 17
GEN
INFO
BREAK-IN PROCEDURES
1. Before starting the engine, fill the fuel
tank with the fuel.
2. Perform the pre-operation checks on the
machine.
3. Start and warm up the engine. Check the
idle speed, and check the operation of
the controls and the “ENGINE STOP”
button. Then, restart the engine and
check its operation within no more than 5
minutes after it is restarted.
4. Operate the machine in the lower gears
at moderate throttle openings for five to
eight minutes.
5. Check how the engine runs when the
motorcycle is ridden with the throttle 1/4
to 1/2 open (low to medium speed) for
about one hour.
6. Restart the engine and check the opera-
tion of the machine throughout its entire
operating range. Restart the machine
and operate it for about 10 to 15 more
minutes. The machine will now be ready
to race.
CAUTION:
lAfter the break-in or before each race,
you must check the entire machine for
loose fittings and fasteners as per
“TORQUE-CHECK POINTS”.
Tighten all such fasteners as required.
lWhen any of the following parts have
been replaced, they must be broken in.
CYLINDER AND CRANKSHAFT:
About one hour of break-in operation is
necessary.
PISTON, RING, VALVES, CAMSHAFTS
AND GEARS:
These parts require about 30 minutes of
break-in operation at half-throttle or less.
Observe the condition of the engine care-
fully during operation.
STARTING AND BREAK-IN

6 - 4
–+ELECIGNITION SYSTEM
EC622001
SPARK GAP TEST
1. Disconnect the spark plug cap from spark
plug.
2. Connect the dynamic spark tester 1
(ignition checker 2) as shown.
lSpark plug cap 3
lSpark plug 4
For USA and CDN
õExcept for USA and CDN
3. Kick the kick starter.
4. Check the ignition spark gap.
5. Start engine, and increase spark gap until
misfire occurs. (for USA and CDN only)
Minimum spark gap:
6.0 mm (0.24 in)

õ
EC624000
COUPLERS AND LEADS CONNECTION
INSPECTION
1. Check:
lCouplers and leads connection
Rust/dust/looseness/short-circuit ®
Repair or replace.
EC625001
“ENGINE STOP” BUTTON INSPECTION
1. Inspect:
l“ENGINE STOP” button conduct
No continuity while being pushed ® Replace.
Continuity while being freed ® Replace. Tester (+) lead ® Black/White lead 1
Tester (–) lead ® Black lead 2
B/W
1B
2Tester selec-
tor position
PUSH IN
W ´ 1
FREE