2003 YAMAHA BIG BEAR PRO 400 boot

Tires ....................................................5-21
How to measure tire pressure .............5-25
Tire wear limit......................................5-27
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
Reverse lock release wire ...................6-15
Shifting ................................................6-17
To start out and accelerate: ................6-19
To decelerate: .....................................6-21
Engine break-in ...................................6-23
Parking ................................................6-27
Parking on a slope ..............................6-27
Accessories and loading .....................6-29
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
67
Crossing through shallow water ......... 7-65
Riding over rough terrain .................... 7-69
Sliding and skidding............................ 7-71
What to do if ... ................................... 7-75
What to do ... ...................................... 7-75
PERIODIC MAINTENANCE AND
ADJUSTMENT ......................................... 8-1
Owner’s manual and tool kit ................. 8-3
Periodic maintenance/lubrication.......... 8-7
Engine oil ............................................ 8-13
Transfer gear oil replacement............. 8-23
Final gear oil ....................................... 8-27
Differential gear oil replacement ......... 8-31
Axle boots ........................................... 8-35
Spark plug inspection ......................... 8-37
Air filter cleaning ................................. 8-43
Carburetor adjustment ........................ 8-49
Idle speed adjustment ........................ 8-51
Valve clearance adjustment ............... 8-53
Select lever safety system
cable adjustment .............................. 8-53
Throttle lever adjustment .................... 8-55
Front brake pad inspection ................. 8-55
Rear brake shoe inspection ................ 8-57
Brake fluid level inspection ................. 8-57
Brake fluid replacement ...................... 8-61
8
U4SH6A.book Page 2 Thursday, May 30, 2002 1:25 PM

2-3

Never allow a child under age 16 to operate an
ATV without adult supervision, and never allow
continued use of an ATV by a child if he or she
does not have the abilities to operate it safely.


Never carry passenger on an ATV.


Always avoid operating an ATV on any paved
surfaces, including sidewalks, driveways, park-
ing lots and streets.


Never operate an ATV on any public street,
road or highway, even a dirt or gravel one.


Never operate an ATV without wearing an ap-
proved motorcycle helmet that fits properly.
You should also wear eye protection (goggles
or face shield), gloves, boots, long-sleeved
shirt or jacket, and long pants.


Never consume alcohol or drugs before or
while operating this ATV.


Never operate at speeds too fast for your skills
or the conditions. Always go at a speed that is
proper for the terrain, visibility and operating
conditions, and your experience.
U4SH6A.book Page 3 Thursday, May 30, 2002 1:25 PM

5-1
EBU00113
1-PRE-OPERATION CHECKS
Before using this machine, check the following points:
ITEM ROUTINE PAGE
Front brakeCheck operation, free play, fluid level and fluid leakage.
Fill with DOT 4 brake fluid if necessary.5-5–5-7,
8-55–8-75
Rear brakeCheck operation, pedal height and free play.
FuelCheck fuel level.
Fill with fuel if necessary.5-9–5-11
Engine oil/
Transfer gear oilCheck oil level.
Fill with oil if necessary.5-13–5-15,
8-13–8-25
Final gear oil/
Differential gear oilCheck for leakage. 5-17, 8-27–8-35
ThrottleCheck for proper throttle cable operation. 5-17, 8-55
Wheels and tiresCheck tire pressure, wear and damage.5-21–5-27,
8-81–8-83
Fittings and FastenersCheck all fittings and fasteners. 5-19
LightsCheck for proper operation. 5-19, 8-91–8-95
Axle bootsCheck operation. 8-35
U4SH6A.book Page 1 Thursday, May 30, 2002 1:25 PM

7-11 1. Protective clothing 2. Goggles
3. Gloves 4. Boots
5. Helmet
1. Vêtement de protection 2. Lunettes
3. Gants 4. Bottes
5. Casque
1. Vestimenta adequada 2. Gafas
3. Guantes 4. Botas
5. Homologado
Apparel
Always wear an approved helmet that fits properly.
You should also wear:
eye protection
(goggles or face shield)
gloves
boots
long-sleeved shirt or jacket
long pants
WARNING
_ Never operate this ATV without wearing an ap-
proved motorcycle helmet, eye protection and
protective clothing. Operating without an ap-
proved motorcycle helmet increases your
chances of a severe head injury or death in the
event of an accident. Operating without eye
protection can result in an accident and in-
creases your chances of a severe injury in the
event of an accident. Operating without protec-
tive clothing increases your chances of severe
injury in the event of an accident. _
U4SH6A.book Page 11 Thursday, May 30, 2002 1:25 PM

8-8 * It is recommended that these items be serviced by a Yamaha dealer.
NOTE:

Recommended brake fluid: DOT 4


Brake fluid replacement:
1. When disassembling the master cylinder or caliper cylinder, replace the brake fluid. Normally check
the brake fluid level and add fluid as required.
2. On the inner parts of the master cylinder and caliper cylinder, replace the oil seals every two years.
3. Replace the brake hoses every four years, or if cracked or damaged.
Drive select lever
safety system*•Check operation.
•Adjust if necessary.Wheels*•Check balance/damage/runout.
•Repair if necessary.Wheel bearing*•Check bearing assemblies for looseness/damage.
•Replace if damaged.Steering system*•Check operation.
•Replace if damaged.
•Check toe-in.
•Adjust if necessary.Axle boots*•Check condition.
•Replace if damaged.Fittings and Fasteners*•Check all chassis fittings and fasteners.
•Correct if necessary.
ITEM ROUTINEINITIAL EVERY
1
month3
months6
months6
months1
year
U4SH6A.book Page 8 Thursday, May 30, 2002 1:25 PM

8-35 1. Boot (× 2)
1. Soufflet (× 2)
1. Guardapolvo (× 2)
1. Boot (× 2)
1. Soufflet (× 2)
1. Guardapolvo (× 2)
6. Install the filler bolt and tighten it to specifica-
tion.
7. Check for oil leakage. If oil leakage is found,
check for the cause.
EBU00862
Axle boots
Check the protective boots for holes or tears. If any
damage is found, have them replaced by a
Yamaha dealer.Tightening torque:
Filler bolt (differential gear case):
23 Nm (2.3 m·kgf)
U4SH6A.book Page 35 Thursday, May 30, 2002 1:25 PM