2005 YAMAHA BRUIN 250 air filter

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 ......................................6-19
Engine break-in ...................................6-21
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 ................................7-41
Climbing uphill.....................................7-47
Riding downhill ....................................7-57
Crossing a slope .................................7-61
Crossing through shallow water ..........7-65
Riding over rough terrain ....................7-71
Sliding and skidding ............................7-73
What to do if ........................................7-77
What to do...........................................7-77
67
PERIODIC MAINTENANCE AND
ADJUSTMENT ......................................... 8-1
Owner’s manual and tool kit ................. 8-3
Periodic maintenance/lubrication.......... 8-7
Engine oil and oil filter element........... 8-17
Final gear oil ....................................... 8-31
Spark plug inspection ......................... 8-37
Air filter element cleaning ................... 8-43
Carburetor adjustment ....................... 8-49
Idle speed adjustment ........................ 8-51
Valve clearance adjustment .............. 8-53
Throttle lever adjustment ................... 8-53
Select lever safety system cable
adjustment ........................................ 8-55
Front brake pad check ........................ 8-55
Rear brake shoe inspection ............... 8-57
Brake fluid level check ........................ 8-59
Brake fluid replacement ...................... 8-61
Front brake lever free play.................. 8-63
Adjusting the brake pedal and rear
brake lever........................................ 8-65
Adjusting the rear brake light switch ... 8-73
Clutch adjustment ............................... 8-75
Cable inspection and lubrication......... 8-77
Brake lever and brake pedal
lubrication ........................................ 8-79
Steering shaft lubrication .................... 8-81
8
U1P060.book Page 2 Monday, August 2, 2004 12:19 PM

3-1
EBU00032
1-DESCRIPTION AND MACHINE
IDENTIFICATION1. Storage compartment
2. Air filter case
3. Engine oil dipstick
4. Front brake fluid reservoir
5. Brake pedal
6. Clutch adjusting bolt
7. Engine oil filter element
8. Rear brake light switch
9. Headlight
10. Fuel cock
11. Recoil starter
12. Fuses
13. Battery
14. Tail/brake light15. Rear shock absorber
spring preload adjusting
ring
16. Engine oil drain bolt
17. Shift pedal
18. Rear brake lever
19. Handlebar switch
20. Parking brake
21. Horn switch
22. Starter (choke)
23. Drive select lever
24. Main switch
25. Fuel tank cap
26. Throttle lever
27. Front brake leverNOTE:The machine you have purchased may differ
slightly from those shown in the figures of this
manual.
U1P060.book Page 1 Monday, August 2, 2004 12:19 PM

7-67
1. Air filter case check hose
1. Flexible de contrôle du boîtier du filtre à air
1. Manguito de retención de la caja del filtro de aire
Test your brakes after leaving the water. Do not
continue to ride your ATV without verifying that
you have regained proper braking ability.CAUTION:_ After riding your ATV in water, be sure to drain
the trapped water by removing the check hose
at the bottom of the air filter case, the drive se-
lect lever box check hose, and the storage
compartment check hose. Wash the ATV in
fresh water if it has been operated in salt water
or muddy conditions. _
U1P060.book Page 67 Monday, August 2, 2004 12:19 PM

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 starter (choke) operation.
Adjust engine idling speed.Cylinder head 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 element
Clean.U1P060.book Page 7 Monday, August 2, 2004 12:19 PM

8-43 1. Air filter case check hose
1. Flexible de contrôle du boîtier du filtre à air
1. Manguito de retención de la caja del filtro de aire
1. Air filter case cover 2. Holder (× 3)
1. Couvercle du boîtier de filtre à air 2. Support (× 3)
1. Tapa de la caja del filtro de aire 2. Soporte (× 3)
EBU10862
Air filter element cleaningNOTE:_ There is a check hose at the bottom of the air filter
case. If dust or water collects in this hose, empty
the hose and clean the air filter element and air fil-
ter case. _1. Remove the seat. (See page 4-27 for seat re-
moval and installation procedures.)
2. Remove the air filter case cover by unhook-
ing the holders.
U1P060.book Page 43 Monday, August 2, 2004 12:19 PM

8-45 1. Air filter element
1.Élément du filtre à air
1. Elemento del filtro de aire
1. Air filter element 2. Foam cover
1.Élément du filtre à air 2. Cache en mousse
1. Elemento del filtro de aire 2. Forro de espuma
3. Pull the air filter element out.
4. Remove the foam cover from the air filter ele-
ment.
5. Wash the foam cover gently but thoroughly in
water or solvent.
WARNING
_ When using solvent to clean the foam cover,
always use parts cleaning solvent. Never use
low flash point solvents or gasoline to clean
the foam cover because the engine could
catch fire or explode. _6. Squeeze the excess solvent out of the foam
cover and let it dry.CAUTION:_

Do not twist the foam cover when squeez-
ing it.


Do not apply oil to the foam cover.
_
U1P060.book Page 45 Monday, August 2, 2004 12:19 PM

8-47
7. Tap the air filter element lightly to remove
most of the dust and dirt. Blow out the re-
maining dirt with compressed air as shown. If
the air filter element is damaged, replace it.NOTE:_ Check the foam cover for damage and replace it if
necessary. _8. Install the foam cover onto the air filter ele-
ment.
9. Install the air filter element.
10. Install the air filter case cover by fastening the
holders.
11. Install the seat.NOTE:_ The air filter element should be cleaned every 20–
40 hours. It should be cleaned more often if the
ATV is operated in extremely dusty areas. Each
time air filter element maintenance is performed,
check the air inlet to the air filter case for obstruc-
tions. Check the air filter element rubber 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. _
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8-49
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. _
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.
U1P060.book Page 49 Monday, August 2, 2004 12:19 PM