2004 YAMAHA YFM50S engine oil

LOCATION OF THE WARNING AND
SPECIFICATION LABELS .......................1-1
SAFETY INFORMATION .........................2-1
DESCRIPTION AND MACHINE
IDENTIFICATION.....................................3-1
Identification number records ...............3-3
Key identification number .....................3-5
Vehicle identification number ...............3-7
Model label ...........................................3-9
CONTROL FUNCTIONS..........................4-1
Main switch ...........................................4-1
Indicator lights ......................................4-3
Handlebar switches ..............................4-3
Engine stop switch with cord (lanyard).....4-7
Throttle lever ......................................4-11
Speed limiter ......................................4-13
Front brake lever ................................4-17Rear brake lever .................................4-17
Parking brake .....................................4-19
Shift lever ...........................................4-21
Fuel tank cap ......................................4-21
Fuel cock ............................................4-23
Choke lever ........................................4-25
Seat ....................................................4-27
PRE-OPERATION CHECKS ...................5-1
Front and rear brakes ...........................5-5
Fuel ......................................................5-9
Engine oil ............................................5-11
Final gear oil .......................................5-15
Throttle lever ......................................5-17
Fittings and fasteners .........................5-17
Switches .............................................5-17
Battery ................................................5-17
Tires ...................................................5-19
How to measure tire pressure ............5-23
Tire wear limit .....................................5-25
EBU00015
CONTENTS
1
2
3
4
5
5YF-9-60 ~3 4/24/03 7:40 PM Page 14

OPERATION ............................................6-1
Starting a cold engine ...........................6-3
Starting a warm engine ......................6-11
Warming up ........................................6-11
To start out and accelerate .................6-13
To decelerate .....................................6-17
Engine break-in ..................................6-19
Parking ...............................................6-23
Parking on a slope ..............................6-25
Accessories and loading ....................6-27
Riding Your ATV ......................................7-1
Getting to know your ATV.....................7-3
Ride with care and good
judgement ...........................................7-5
Be careful where you ride ...................7-27
Turning your ATV ...............................7-39
Climbing uphill ....................................7-43
Riding downhill ...................................7-55
Crossing a slope .................................7-59
Crossing through shallow water .........7-63Riding over rough terrain ....................7-67
Sliding and skidding ...........................7-69
What to do if ......................................7-73
What to do .........................................7-73
PERIODIC MAINTENANCE AND
ADJUSTMENT .........................................8-1
Owner’s manual and tool kit .................8-3
Periodic maintenance/lubrication .........8-7
Engine oil ............................................8-13
Final gear oil .......................................8-19
Spark plug inspection .........................8-23
Air filter cleaning .................................8-27
Carburetor adjustment ........................8-35
Idle speed adjustment ........................8-37
Valve clearance adjustment ...............8-39
Cam chain adjustment ........................8-39
Front and rear brake shoe
inspection .........................................8-41
Front brake lever free play
adjustment ........................................8-436
7
8
5YF-9-60 ~3 4/24/03 7:40 PM Page 15

5-1
EBU00113
PRE-OPERATION CHECKS
Before using this machine, check the following points:
ITEM ROUTINE PAGE
Brakes9Check operation, condition and free play.
5-5–5-7, 8-41–8-49
9Adjust if necessary.
Fuel9Check fuel level.
9Fill with fuel if necessary.5-9–5-11
Engine oil9Check oil level.
9Fill with oil if necessary.5-11–5-13, 8-13–8-17
Final gear oil9Check for leakage. 5-15, 8-19–8-21
Throttle9Check for proper throttle cable operation. 5-17
Wheels and tires9Check tire pressure, wear and damage. 5-19–5-25, 8-55
Fittings and fasteners9Check all fittings and fasteners. 5-17
Switches9Check operation. 5-17
Battery9Check fluid level.
5-17, 8-57–8-63
9Fill with distilled water if necessary.
5YF-9-60 4~5 4/24/03 7:41 PM Page 28

5-11
w
8Do not overfill the fuel tank. Fuel expands
when it heats up. If the fuel tank is over-
filled, fuel could spill out due to heat from
the engine or the sun.
8Be careful not to spill fuel, especially on
the engine or exhaust pipe which can
cause a fire and severe injury. Wipe up
any spilled fuel immediately.
8Do not refuel right after the engine has
been running and is still very hot.
8Be sure the fuel tank cap is closed secure-
ly.
EBU10842
Engine oil
Make sure the engine oil is at the specified level.
Add oil as necessary. (See page 8-13.)
5YF-9-60 4~5 4/24/03 7:41 PM Page 38

5-13
cC
8In order to prevent clutch slippage (since
the engine oil also lubricates the clutch),
do not mix any chemical additives. Do not
use oils with a diesel specification of “CD”
or oils of a higher quality than specified. In
addition, do not use oils labeled “ENERGY
CONSERVING
II” or higher.
8Make sure that no foreign material enters
the crankcase.
Recommended engine oil type and quantity:
See page 10-2.
5YF-9-60 4~5 4/24/03 7:41 PM Page 40

8-7
EBU00262
PERIODIC MAINTENANCE/LUBRICATION
INITIAL EVERY
ITEM ROUTINE 1 3 6 6 1
month months months months year
Valves*9Check valve clearance.
9Adjust if necessary.2 222
Cam chain*9Check chain tension.
9Adjust if necessary.2 222
9Check condition.
Spark plug9Adjust gap and clean.22222
9Replace if necessary.
Air filter element9Clean. Every 20–40 hours.
9Replace if necessary. (more often in wet or dusty areas)
Carburetor*9Check idle speed/choke lever operation.
2222
9Adjust if necessary.
Crankcase breather9Check breather hose for cracks or damage.
system*9Replace if necessary.222
9Check for leakage.
Exhaust system*9Tighten if necessary.222
9Replace gasket if necessary.
Fuel line*9Check fuel hose for cracks or damage.
222
9Replace if necessary.
Engine oil9Replace (warm engine before draining).2 222
Final gear oil9Check oil level/oil leakage.
22
9Replace every 12 months.
Brakes*9Check operation.
22222
9Adjust if necessary.
5YF-9-60 8 4/24/03 6:35 PM Page 8-7

8-13
EBU14181
Engine oil
Engine oil level measurement
1. Place the ATV on a level surface.
2. Warm up the engine for several minutes
and stop it.
3. Remove the dipstick and wipe it off with a
clean rag. Insert the dipstick in the filler
hole without screwing it in.
NOTE:
Wait a few minutes until the oil level settles
before checking.
4. Remove the dipstick and inspect the oil
level.
5. The oil level should be between the mini-
mum and maximum marks. If the level is
low, add oil to raise it to the specified level.
cC
Be sure no foreign material enters the
crankcase.
12
3
1. Dipstick
2. Maximum level mark 3. Minimum level mark
1. Jauge
2. Repère de niveau maximum 3. Repère de niveau minimum
1. Varilla de medición
2. Marca de máximo 3. Marca de mínimo
5YF-9-60 8 4/24/03 6:35 PM Page 8-13

8-15
Engine oil replacement
1. Place the ATV on a level surface.
2. Warm up the engine for several minutes
and stop it.
3. Place a container under the engine.
4. Remove the dipstick and drain bolt to drain
the oil.
5. Inspect the O-ring and replace if damaged.
6. Install the drain bolt and tighten to specifi-
cation.
1
1. Drain bolt1. Bouchon de vidange1. Perno de drenaje
Tightening torque
Drain bolt:
20 Nm (2.0 m0kgf)
5YF-9-60 8 4/24/03 6:35 PM Page 8-15