
PERIODIC MAINTENANCE AND MINOR REPAIR
6-12
2
3
4
5
6
7
8
9
EAU34171
Checking the spark plug
The spark plug is an important engine
component, which is easy to check.
Since heat and deposits will cause any
spark plug to slowly erode, the spark
plug should be removed and checked
in accordance with the periodic mainte-
nance and lubrication chart. In addition,
the condition of the spark plug can re-
veal the condition of the engine.
To remove the spark plug
1. Open the rider seat. (See
page 3-11.)
2. Pull up the storage compartment
mat, and then remove the spark
plug cover by removing the
screws.
3. Remove the spark plug cap.
4. Remove the spark plug as shown,
with the spark plug wrench includ-
ed in the owner’s tool kit.
To check the spark plug
1. Check that the porcelain insulator
around the center electrode of the
spark plug is a medium-to-light tan
(the ideal color when the vehicle is
ridden normally).
NOTE:
If the spark plug shows a distinctly dif-
ferent color, the engine could be defec-
tive. Do not attempt to diagnose such
problems yourself. Instead, have a
Yamaha dealer check the vehicle.
2. Check the spark plug for electrode
erosion and excessive carbon or
other deposits, and replace it if
1. Storage compartment mat
2. Spark plug cover
3. Screw
1. Spark plug cap
1
2
3
(
×
3)
1
1. Spark plug wrench
1
Summary of Contents for MAJESTY 400
Page 1: ...5RU 28199 10 YP400T OWNER S MANUAL ...
Page 2: ......
Page 7: ...TABLE OF CONTENTS ...
Page 12: ...1 5 ...
Page 13: ...SAFETY INFORMATION 1 6 1 EAU10381 ly before operating this vehicle 2 1 3 5 6 7 4 ...
Page 15: ...SAFETY INFORMATION 1 8 1 ...
Page 17: ...DESCRIPTION 2 2 2 3 4 5 6 7 8 9 EAU10420 5 3 4 ...
Page 80: ...ND MINOR REPAIR 6 39 ...
Page 89: ...SPECIFICATIONS 8 3 2 3 4 5 6 7 8 9 tor fan fuse 0 A onic fuel injection fuse 0 A p fuse 0 A ...
Page 91: ...CONSUMER INFORMATION 9 2 2 3 4 5 6 7 8 9 ...
Page 94: ...9 5 Mileage Servicing dealer name and address Remarks ...
Page 95: ...CONSUMER INFORMATION 9 6 2 3 4 5 6 7 8 9 EAU26661 U S A STREET AND ENDURO MOTORCYCLE LIMITED ...
Page 96: ...9 7 ...
Page 98: ...9 9 benefits of y knowing after your maha with We ll be d ...
Page 100: ......
Page 101: ...YAMAHA MOTOR CO LTD PRINTED IN JAPAN 2004 7 1 7 1 E ...