Yamaha BIG BEAR YFM400FWS User manual

5FU-F8199-14LIT-11626-17-10
READ THIS MANUAL CAREFULLY!
It contains important safety information.
This ATV should not be ridden by anyone under 16 years of age.
WARNING
YFM400FWS
OWNER’S MANUAL
PRINTED IN USA
2003.04-2.4×1 CR
(E)
PRINTED ON RECYCLED PAPER
YAMAHA MOTOR CO., LTD.
EBU00438
LOCATE AND READ OWNER’S MANUAL. FOLLOW ALL INSTRUCTIONS AND WARNINGS.
(For replacement manual, call 1-800-532-1558)
WARNING
ALWAYS:
use proper riding techniques to avoid
vehicle overturns on hills and rough
terrain and in turns.
avoid paved surfaces-pavement may
seriously affect handling and control.
Improper ATV use can result in SEVERE INJURY or DEATH.
NEVER operate:
without proper training or instruction.
at speeds too fast for your skills or the
conditions.
on public roads-a collision can occur with
another vehicle.
with a passenger-passengers affect
balance and steering and increase risk
of losing control.
ALWAYS USE
AN APPROVED
HELMET AND
PROTECTIVE GEAR
NEVER USE
ON PUBLIC
ROADS
NEVER CARRY
PASSENGERS
NEVER USE
WITH DRUGS
OR ALCOHOL
B
E
E
R
B
EE
R

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1-
INTRODUCTION
Congratulations on your purchase of the Yamaha YFM400FW. It represents the result of many
years of Yamaha experience in the production of fine sporting, touring, and pace-setting racing
machines. With the purchase of this Yamaha, you can now appreciate the high degree of crafts-
manship and reliability that have made Yamaha a leader in these fields.
This manual will provide you with a good basic understanding of the features and operation of this
ATV. This manual includes important safety information. It provides information about
special techniques and skills necessary to ride your ATV. It also includes basic maintenance
and inspection procedures. If you have any questions regarding the operation or maintenance of
your ATV, please consult a Yamaha dealer.
AN IMPORTANT SAFETY MESSAGE:
●READ THIS MANUAL TOGETHER WITH TIPS FOR THE ATV RIDER CAREFULLY AND
COMPLETELY BEFORE OPERATING YOUR ATV. MAKE SURE YOU UNDERSTAND ALL
INSTRUCTIONS.
●PAY CLOSE ATTENTION TO THE WARNING AND CAUTION LABELS ON THE ATV.
●NEVER OPERATE AN ATV WITHOUT PROPER TRAINING OR INSTRUCTION. FREE
TRAINING IS AVAILABLE TO ANYONE WHO BUYS A NEW ATV. CALL 1-800-887-2887
FOR MORE INFORMATION.
●THIS ATV, AND ANY OTHER ATV OVER 90cc, SHOULD NOT BE RIDDEN BY ANYONE
UNDER 16 YEARS OF AGE.
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1-
IMPORTANT MANUAL INFORMATION
FAILURE TO FOLLOW THE WARNINGS CONTAINED IN THIS MANUAL CAN RESULT IN
SERIOUS INJURY OR DEATH.
Particularly important information is distinguished in this manual by the following notations:
The Safety Alert Symbol means ATTENTION! BECOME ALERT!
YOUR SAFETY IS INVOLVED!
WARNING
Failure to follow WARNING instructions could result in severe
injury or death to the machine operator, a bystander or a person
inspecting or repairing the machine.
CAUTION:
A CAUTION indicates special precautions that must be taken to
avoid damage to the machine.
NOTE:
A NOTE provides key information to make procedures easier or clearer.
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EBU00011
IMPORTANT NOTICE
This machine is designed and manufactured for OFF-ROAD use only. It is illegal and unsafe to
operate this machine on any public street, road or highway.
This machine complies with all applicable OFF-ROAD noise level and spark arrester laws and
regulations in effect at the time of manufacture.
Please check your local riding laws and regulations before operating this machine.
EBU01067
AFFIX DEALER
LABEL HERE
YFM400FWS
OWNER’S MANUAL
©2003 by Yamaha Motor Corporation,
U.S.A.
1st edition, March 2003
All rights reserved. Any reprinting or
unauthorized use without the written
permission of
Yamaha Motor Corporation,
U.S.A. is expressly prohibited.
Printed in U.S.A.
P/N LIT-11626-17-10
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EBU00014
WARNING
Indicates a potential hazard that could
result in serious injury or death.
CONTENTS
LOCATION OF THE WARNING
AND SPECIFICATION LABELS....... 1-1
SAFETY INFORMATION.................. 2-1
DESCRIPTION AND MACHINE
IDENTIFICATION ............................. 3-1
Identification number records.......... 3-2
Key identification number................ 3-2
Vehicle identification number .......... 3-3
Model label ...................................... 3-3
1
2
3
CONTROL FUNCTIONS...................4-1
Main switch ......................................4-1
Indicator and warning lights.............4-2
Speedometer ...................................4-4
Fuel gauge .......................................4-4
Handlebar switches .........................4-5
Throttle lever ....................................4-7
Speed limiter ....................................4-8
Front brake lever..............................4-9
Brake pedal and rear brake
lever ...............................................4-9
Parking brake.................................4-10
Shift pedal ......................................4-11
Reverse knob.................................4-11
Recoil starter..................................4-12
Fuel tank cap .................................4-13
Fuel cock........................................4-13
Starter (choke) ...............................4-14
Seat................................................4-15
Storage box....................................4-16
Front carrier ...................................4-16
Rear carrier ....................................4-16
4
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Front shock absorber
adjustment................................... 4-17
Rear shock absorber
adjustment................................... 4-18
Auxiliary DC jack........................... 4-19
PRE-OPERATION CHECKS ........... 5-1
Front and rear brakes ..................... 5-3
Fuel ................................................. 5-5
Engine oil ........................................ 5-7
Final gear oil.................................... 5-7
Differential gear oil .......................... 5-8
Throttle lever ................................... 5-8
Fittings and fasteners...................... 5-8
Lights............................................... 5-8
Switches.......................................... 5-8
Tires ................................................ 5-9
How to measure tire pressure....... 5-11
Tire wear limit................................ 5-12
OPERATION ..................................... 6-1
Starting a cold engine...................... 6-1
Starting a warm engine ................... 6-3
Warming up ..................................... 6-3
Reverse knob operation and
reverse driving ............................... 6-4
Shifting............................................. 6-5
To start out and accelerate.............. 6-5
To decelerate................................... 6-6
Engine break-in ............................... 6-7
Parking............................................. 6-8
Parking on a slope........................... 6-9
Accessories and loading ............... 6-10
RIDING YOUR ATV .......................... 7-1
Getting to know your ATV ............... 7-3
Ride with care and good
judgement...................................... 7-4
Be careful where you ride..............7-16
Turning your ATV .......................... 7-23
Climbing uphill ............................... 7-25
Riding downhill .............................. 7-30
Crossing a slope............................7-32
5
6
7
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Crossing through shallow water.... 7-34
Riding over rough terrain............... 7-36
Sliding and skidding ...................... 7-38
What to do if .................................. 7-40
What to do ..................................... 7-40
PERIODIC MAINTENANCE AND
ADJUSTMENT.................................. 8-1
Owner’s manual and tool kit............ 8-1
Periodic maintenance/
lubrication ...................................... 8-3
Engine oil and oil filter element ....... 8-5
Final gear oil .................................... 8-9
Differential gear oil......................... 8-12
Axle boots...................................... 8-14
Spark plug inspection.................... 8-14
Air filter element cleaning.............. 8-15
Spark arrester cleaning ................. 8-19
Carburetor adjustment................... 8-20
Idle speed adjustment ................... 8-21
Valve clearance adjustment.......... 8-22
Throttle lever adjustment............... 8-22
Front brake pad check .................. 8-23
Rear brake shoe inspection...........8-23
Brake fluid level check ...................8-24
Brake fluid replacement .................8-25
Front brake lever free play.............8-26
Rear brake pedal and lever
adjustment ...................................8-27
Adjusting the rear brake light
switch ...........................................8-30
Clutch adjustment ..........................8-30
Cable inspection and lubrication....8-31
Brake and shift pedal/
brake lever lubrication..................8-32
Wheel removal...............................8-32
Wheel installation...........................8-33
Battery............................................8-34
Battery maintenance......................8-35
Fuse replacement ..........................8-35
Replacing a headlight bulb ............8-37
Headlight beam adjustment...........8-39
Tail/brake light bulb
replacement .................................8-40
Troubleshooting .............................8-41
Troubleshooting chart ....................8-43
8
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CLEANING AND STORAGE............ 9-1
A. Cleaning...................................... 9-1
B. Storage ....................................... 9-3
SPECIFICATIONS.......................... 10-1
NOISE REGULATION.................... 11-1
MAINTENANCE RECORD ............ 12-1
ATV LIMITED WARRANTY............ 13-1
YAMAHA EXTENDED SERVICE
(Y.E.S.) ........................................... 14-1
9
10
11
12
13
14
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1-1
EBU00464
LOCATION OF THE WARNING AND
SPECIFICATION LABELS
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