Carburetor YAMAHA BRUIN 350 2005 Owners Manual

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
Engine break-in ...................................6-15
Parking ................................................6-17
Parking on a slope ..............................6-19
Accessories and loading .....................6-21
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 ....................7-69
Sliding and skidding ............................7-71
What to do if .......................................7-75
What to do ..........................................7-75
67
PERIODIC MAINTENANCE AND
ADJUSTMENT ........................................ 8-1
Owner’s manual and tool kit ................. 8-3
Periodic maintenance/lubrication.......... 8-7
Panel removal and installation............ 8-17
Engine oil and oil filter cartridge ......... 8-21
Final gear oil ....................................... 8-31
Differential gear oil replacement ......... 8-39
Axle boots ........................................... 8-45
Spark plug inspection ......................... 8-47
Air filter element cleaning ................... 8-53
V-belt cooling duct check hose ........... 8-61
V-belt case drain plug ......................... 8-61
Carburetor adjustment ........................ 8-63
Idle speed adjustment ........................ 8-65
Valve clearance adjustment ............... 8-67
Select lever safety system cable
adjustment ........................................ 8-67
Throttle lever adjustment .................... 8-69
Front brake pad check ........................ 8-71
Rear brake shoe inspection ................ 8-71
Brake fluid level check ........................ 8-73
Brake fluid replacement ...................... 8-77
Front brake lever free play.................. 8-79
Rear brake pedal and lever
adjustment ........................................ 8-81
8
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2-15
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.
_
U5UH61.book Page 15 Tuesday, April 20, 2004 10:10 AM

4-33 1. Arrow mark pointing to “OFF”
1. Flèche dirigée vers “OFF”
1. Marca de la flecha señalando a “OFF”
OFF position
Robinet fermé
Posición OFF1. Arrow mark pointing to “ON”
1. Flèche dirigée vers “ON”
1. Marca de la flecha señalando a “ON”ON position
Robinet ouvert
Posición ON
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.
ON: With the lever in this position, fuel flows to
the carburetor. Normal riding is done with
the lever in this position.
U5UH61.book Page 33 Tuesday, April 20, 2004 10:10 AM

8-7
EBU02621
PERIODIC MAINTENANCE/LUBRICATION
NOTE:_

For ATVs not equipped with an odometer or an hour meter, follow the month maintenance intervals.


For ATVs equipped with an odometer or an hour meter, follow the km (mi) or hours maintenance intervals. How-
ever, keep in mind that if the ATV isn’t used for a long period of time, the month maintenance intervals should be
followed.
_
ITEM ROUTINEWhichever
comes firstINITIAL EVERY
month136612
km
(mi)320
(200)1,200
(750)2,400
(1,500)2,400
(1,500)4,800
(3,000)
hours 20 75 150 150 300
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 and adjust idle speed/starter operation.
Adjust if necessary.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 cartridge
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8-59
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. _
U5UH61.book Page 59 Tuesday, April 20, 2004 10:10 AM

8-63
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.
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10-3
Final gear oil:
Type SAE 80 API GL-4 Hypoid gear oil
Quantity 0.23 L
Differential gear oil:
Type SAE 80 API GL-4 Hypoid gear oil
Quantity 0.35 L
Air filter: Wet element
Fuel:
Type Unleaded gasoline only
For Europe: Regular unleaded gasoline only with a
research octane number of 91 or higher
Fuel tank capacity 13.5 L
Fuel reserve amount 3.3 L
Carburetor:
Type/quantity BSR33/1
Manufacturer MIKUNI
Spark plug:
Type/manufacturer DR8EA / NGK
Spark plug gap 0.6–0.7 mm
Clutch type: Wet, centrifugal automaticModel YFM350FA
U5UH61.book Page 3 Tuesday, April 20, 2004 10:10 AM