2004 YAMAHA YFM350R carburetor

OPERATION ............................................6-1
Starting a cold engine ...........................6-3
Starting a warm engine .........................6-9
Warming up...........................................6-9
Drive select lever operation and
reverse driving ..................................6-11
Shifting ................................................6-15
To start out and accelerate .................6-17
To decelerate ......................................6-21
Engine break-in ...................................6-23
Parking ................................................6-27
Parking on a slope ..............................6-27
Accessories and loading .....................6-31
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.....................................7-45
Riding downhill ....................................7-55
Crossing a slope .................................7-59
Crossing through shallow water ..........7-63
Riding over rough terrain ....................7-67
SLIDING AND SKIDDING...................7-69
What to do if .......................................7-73
What to do ..........................................7-73
67
PERIODIC MAINTENANCE AND ADJUST-
MENT ....................................................... 8-1
Owner’s manual and tool kit ................. 8-3
Periodic maintenance/lubrication.......... 8-7
Engine oil and oil filter element........... 8-15
Spark plug inspection ......................... 8-27
Air filter element cleaning ................... 8-31
Carburetor adjustment ........................ 8-39
Idle speed adjustment ........................ 8-41
Throttle lever adjustment .................... 8-43
Valve clearance adjustment ............... 8-43
Front brake pad inspection ................. 8-45
Rear brake pad inspection.................. 8-45
Brake fluid level check ........................ 8-47
Brake fluid replacement ...................... 8-51
Front brake lever free play.................. 8-53
Brake pedal height adjustment ........... 8-55
Parking brake adjustment ................... 8-57
Adjusting the rear brake light switch ... 8-63
Clutch lever free play adjustment ....... 8-65
Drive chain slack check ...................... 8-67
Drive chain slack adjustment .............. 8-69
Lubricating the drive chain.................. 8-71
Cable inspection and lubrication......... 8-73
Brake and shift pedal/brake and
clutch lever lubrication ...................... 8-73
8
E_5YTTOC-E.fm Page 2 Friday, December 12, 2003 4:01 PM

2-17
WARNING
_

Always turn off the engine when refueling.


Do not refuel immediately after the engine
has been running and is still very hot.


Do not spill gasoline on the engine or ex-
haust pipe/muffler when refueling. Never
refuel while smoking, or in the vicinity of
sparks, open flames, or other sources of
ignition such as the pilot lights of water
heaters and clothes dryers. Gasoline can
catch fire and you could be burned.


When transporting the ATV in another ve-
hicle, be sure it is kept upright and that the
fuel cock is in the “OFF” position. Other-
wise, fuel may leak out of the carburetor or
fuel tank.


Gasoline is poisonous. If you should swal-
low some gasoline or inhale a lot of gaso-
line vapor, or get some gasoline in your
eyes, see your doctor immediately. If gaso-
line spills on your skin, wash with soap
and water. If gasoline spills on your cloth-
ing, change your clothes.
_
U5YT60.book Page 17 Friday, December 12, 2003 1:55 PM

4-23 1. Fuel tank cap
1. Bouchon de réservoir de carburant
1. Tapón del depósito de combustible
1. Arrow mark pointing to “OFF”
1. Flèche dirigée vers “OFF”
1. Marca de la flecha señalando a “OFF”OFF PositionRobinet fermé
Posición OFF
EBU00092
Fuel tank cap
Remove the fuel tank cap by turning it counter-
clockwise.
EBU00093
Fuel cock
The fuel cock supplies fuel from the fuel tank to the
carburetor.
The fuel cock has three positions.
OFF: With the lever in this position, fuel will not
flow. Always turn the lever to this position
when the engine is not running.
U5YT60.book Page 23 Friday, December 12, 2003 1:55 PM

4-25 1. Arrow mark pointing to “ON”
1. Flèche dirigée vers “ON”
1. Marca de la flecha señalando a “ON”
ON PositionRobinet ouvert
Posición ON1. Arrow mark pointing to “RES”
1. Flèche dirigée vers “RES”
1. Marca de la flecha señalando a “RES”RES PositionRéserve
Posición RES
ON: With the lever in this position, fuel flows to
the carburetor. Normal riding is done with
the lever in this position.
RES: This indicates reserve. If you run out of fuel
while riding, turn the lever to this position.
THEN FILL THE FUEL TANK AT THE
FIRST OPPORTUNITY. After refuelling, re-
turn the fuel cock lever to the “ON” position.
U5YT60.book Page 25 Friday, December 12, 2003 1:55 PM

8-7
EBU00262
PERIODIC MAINTENANCE/LUBRICATION
ITEM ROUTINEINITIAL EVERY
1
month3
months6
months6
months1
year
Valves*Check valve clearance.
Adjust if necessary.
Spark plugCheck condition.
Adjust gap and clean.
Replace if necessary.Air filter elementClean.
Replace if necessary.Every 20–40 hours
(More often in wet or dusty areas.)
Carburetor*Check starter (choke) operation.
Adjust engine idling speed.Crankcase breather
system*Check breather hose for cracks or damage.
Replace if necessary.Exhaust system*Check for leakage.
Tighten if necessary.
Replace gasket(s) if necessary.Fuel line*Check fuel hose for cracks or damage.
Replace if necessary.Engine oil
Replace. (Warm engine before draining.)Engine oil filter elementClean.
Replace if necessary.Engine oil strainer
Clean.Drive chain
Check and adjust slack/alignment/clean/lube.Brakes*Check operation/fluid leakage/See NOTE page 8-8.
Correct if necessary.Clutch*Check operation.
Adjust if necessary.Wheels*Check balance/damage/runout.
Replace if necessary.Wheel bearings*Check bearing assemblies for looseness/damage.
Replace if damaged.U5YT60.book Page 7 Friday, December 12, 2003 1:55 PM

8-37
NOTE:_ The air filter element should be cleaned every 20–
40 hours. It should be cleaned and lubricated more
often if the machine is operated in extremely dusty
areas. Each time the air filter element mainte-
nance is performed, check the air inlet to the filter
case for obstructions. Check the air filter case rub-
ber joint to the carburetor and manifold fittings for
an airtight seal. Tighten all fittings securely to
avoid the possibility of unfiltered air entering the
engine. _CAUTION:_ Never operate the engine with the air filter ele-
ment removed. This will allow unfiltered air to
enter, causing rapid engine wear and possible
engine damage. Additionally, operation with-
out the air filter element will affect carburetor
jetting with subsequent poor performance and
possible engine overheating. _
U5YT60.book Page 37 Friday, December 12, 2003 1:55 PM

8-39
EBU00296
Carburetor adjustment
The carburetor is a vital part of the engine and re-
quires very sophisticated adjustment. Most adjust-
ing should be left to a Yamaha dealer who has the
professional knowledge and experience to do so.
However, the idling speed may be performed by
the owner as a part of the usual maintenance rou-
tine.CAUTION:
The carburetor was set at the Yamaha factory
after many tests. If the settings are disturbed
by someone without sufficient technical
knowledge, poor engine performance and
damage may result.
U5YT60.book Page 39 Friday, December 12, 2003 1:55 PM

10-3
Quantity:
Without oil filter element replacement
With oil filter element replacement2.5 L
2.6 L
Air filter: Wet element
Fuel:
Type
Tank capacity
Reserve amountUnleaded gasoline only
For Europe: Regular unleaded gasoline only with a
research octane number of 91 or higher
9.0 L
2.7 L
Carburetor:
Type
× quantity
ManufacturerBSR36
× 1
MIKUNI
Spark plug:
Type/manufacturer
GapDR8EA / NGK
0.6–0.7 mm
Clutch:
Type
OperationWet, Multiple-disc
Left hand operation
Transmission:
Primary reduction system
Primary reduction ratio
Secondary reduction system
Secondary reduction ratio
Transmission type
OperationSpur gear
76/24 (3.166)
Chain drive
38/13 (2.923)
Constant mesh, 6-speed forward, 1-speed reverse
Left foot operation MODEL YFM350
U5YT60.book Page 3 Friday, December 12, 2003 1:55 PM