2002 YAMAHA YFM80 engine

8-71
EBU00440
Troubleshooting chart
1. Fuel
Check if there is
fuel in the fuel
tank
2. Compression
Use electric starter
to see if there is
compression
3. Ignition
Remove plug and
check electrode
WetWipe clean with dry
cloth
DryAttach plug cap and
ground to chassisUse electric
starterSpark weak
Spark goodIgnition system normal
No spark
Ask a Yamaha dealer to inspect
Adjust plug gap or
replace plug
There is compressonCompression normal
Ask a Yamaha dealer to inspectNo compression
There is fuelTurn the fuel
cock to “OFF”
Remove the
fuel hose from
the fuel cock.
Some fuelTurn the fuel
cock to “RES”Restart engine
No fuelSupply fuel
4. Battery
Use electric
starter
Engine turns
over quicklyBattery good
Engine turns
over slowlyCheck fluid, recharge,
check connections
Check fuel flow
Water or dirt
mixed in fuel
Turn the fuel
cock to “ON”No fuelFuel cock clogged
Clean filter element
and fuel tank
Clean fuel cock
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9-1
EBU00420
CLEANING AND STORAGE
A. CLEANING
Frequent, thorough cleaning of your machine
will not only enhance its appearance but will
improve its general performance and extend the
useful life of many components.
1. Before cleaning the machine:
a. Block off the end of the exhaust pipe to
prevent water entry. A plastic bag and
strong rubber band may be used.
b. Make sure the spark plug and all filler caps
are properly installed.
2. If the engine case is excessively greasy,
apply degreaser with a paint brush. Do not
apply degreaser to the wheel axles.
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9-5
6. Clean the seat with a vinyl upholstery
cleaner to keep the cover pliable and
glossy.
7. Automotive type wax may be applied to all
painted and chrome plated surfaces. Avoid
combination cleaner-waxes. Many contain
abrasives which may mar the paint or pro-
tective finish.
When finished, start the engine and let it
idle for several minutes.
w
Wet brakes may have reduced stopping abili-
ty, increasing the chance of an accident.
Test the brakes after washing. Apply the
brakes several times at slow speeds to let
friction dry out the linings.
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9-7
EBU00427
B. STORAGE
Long term storage (60 days or more) of your
machine will require some preventive proce-
dures to guard against deterioration. After thor-
oughly cleaning the machine, prepare for stor-
age as follows:
1. Fill the fuel tank with fresh fuel and add
fuel stabilizer (if available).
NOTE:
Use of fuel stabilizer eliminates the need to
drain the fuel system. Consult a Yamaha dealer
if the fuel system is to be drained instead.
2. Remove the spark plug, pour about one
tablespoon of SAE 10W30 or 20W40
motor oil in the spark plug hole and rein-
stall the spark plug. Ground the spark plug
wire and turn the engine over several times
to coat the cylinder wall with oil.
3. Lubricate all control cables.
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10-1
Model YFM80
Dimensions:
Overall length 1,520 mm
Overall width 825 mm
Overall height 960 mm
Seat height 650 mm
Wheelbase 1,030 mm
Minimum ground clearance 100 mm
Minimum turning radius 2,000 mm
Basic weight:
With oil and full fuel tank 116 kg
Engine:
Type Air-cooled 4-stroke, SOHC
Cylinder arrangement Single cylinder, forward-inclined
Displacement 79 cm
3
Bore × Stroke 47.0 ×45.6 mm
Compression ratio 9.6 : 1
Starting system Electric starter
Lubrication system: Wet sump
EBU00428
SPECIFICATIONS
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10-2
10
MODEL YFM80
Engine oil:
Type
Recommended engine oil classification: API Service SE, SF, SG type or higher
Quantity:
Periodic oil change 0.80 L
Total amount0.95 L
cC
Be sure to use motor oils that do not contain
anti-friction modifiers. Passenger car motor
oils (often labeled “Energy Conserving”) con-
tain anti-friction additives which will cause
clutch and/or starter clutch slippage, result-
ing in reduced component life and poor
engine performance.
–20° 10° 20° 30° 40°
10W30
10W40
20W40
20W5050°C
0° –10°
5W30
15W40
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