
Periodic maintenance and adjustment
6-9
1
2
3
4
567
8
9
10
11
12
EAU19653
Checking the spark plugsThe spark plugs are important engine
components, which should be checked
periodically, preferably by a Yamaha
dealer. Since heat and deposits will
cause any spark plug to slowly erode,
they should be removed and checked
in accordance with the periodic mainte-
nance and lubrication chart. In addition,
the condition of the spark plugs can re-
veal the condition of the engine.
The porcelain insulator around the cen-
ter electrode of each spark plug should
be a medium-to-light tan (the ideal color
when the vehicle is ridden normally),
and all spark plugs installed in the en-
gine should have the same color. If any
spark plug shows a distinctly different
color, the engine could be operating im-
properly. Do not attempt to diagnose
such problems yourself. Instead, have
a Yamaha dealer check the vehicle.
If a spark plug shows signs of electrode
erosion and excessive carbon or other
deposits, it should be replaced. Before installing a spark plug, the spark
plug gap should be measured with a
wire thickness gauge and, if necessary,
adjusted to specification.
Clean the surface of the spark plug
gasket and its mating surface, and then
wipe off any grime from the spark plug
threads.
TIPIf a torque wrench is not available wheninstalling a spark plug, a good estimate
of the correct torque is 1/4–1/2 turn
past finger tight. However, the spark
plug should be tightened to the speci-
fied torque as soon as possible.NOTICE
ECA10841
Do not use any tools to remove or in-
stall the spark plug cap, otherwise
the ignition coil coupler may get
damaged. The spark plug cap may
be difficult to remove because the
rubber seal on the end of the cap fits
tightly. To remove the spark plug
cap, simply twist it back and forth
while pulling it out; to install it, twistit back and forth while pushing it in.
Specified spark plug:
NGK/CPR9EA9
1. Spark plug gapSpark plug gap:0.8–0.9 mm (0.031–0.035 in)
Tightening torque: Spark plug:13 N·m (1.3 kgf·m, 9.6 lb·ft)
UB90E2.book 9 ページ 2018年6月5日 火曜日 午後5時40分

Periodic maintenance and adjustment
6-12
1
2
3
4
56
7
8
9
10
11
12
TIPMake sure that the O-ring is properlyseated. 6. Install the new oil filter cartridge, and then tighten to the specified
torque. 7. Install the engine oil drain bolt with
a new gasket, and then tighten the
bolt to the specified torque.
8. Pour the specified amount of the recommended oil into the crank-
case.
TIPUsing a funnel is recommended.
9. After checking the engine oil filler cap O-ring, install the filler cap.TIPWipe off any spilled oil before startingthe engine.
10. Start the engine and let it idle for several minutes while checking for
oil leaks. If any leakage is found,
immediately stop the engine and
check for the cause.
NOTICE
ECA10402
If the oil level warning light flickers
or remains on even if the oil level is
correct, immediately turn the engine
off and have a Yamaha dealer checkthe vehicle.
11. Turn the engine off, wait a few min- utes until the oil settles, and then
check the oil level one last time.
1. O-ring
1. Torque wrench
1
Tightening torque:Oil filter cartridge:17 N·m (1.7 kgf·m, 13 lb·ft)
Tightening torque: Engine oil drain bolt:43 N·m (4.3 kgf·m, 32 lb·ft)
UB90E2.book 12 ページ 2018年6月5日 火曜日 午後5時40分

10-1
1
2
3
4
5
6
7
8
910
11
12
IndexAABS ....................................................... 3-17
ABS warning light.................................... 3-5
Air filter element .................................... 6-14
Auxiliary DC connector ......................... 3-30
Auxiliary light bulb, replacing ................ 6-34BBattery................................................... 6-28
Brake and clutch levers, checking and lubricating ........................................... 6-26
Brake and shift pedals, checking and lubricating ........................................... 6-25
Brake fluid, changing ............................ 6-22
Brake fluid level, checking .................... 6-20
Brake lever ............................................ 3-16
Brake lever free play, checking ............. 6-19
Brake light switches .............................. 6-19
Brake pedal ........................................... 3-17
Brake/tail light ....................................... 6-34CCables, checking and lubricating .......... 6-24
Canister................................................. 6-10
Care ........................................................ 7-1
Catalytic converter ................................ 3-22
Clutch lever ........................................... 3-15
Clutch lever free play, adjusting ............ 6-18
Coolant.................................................. 6-13
Coolant temperature warning light .......... 3-4DData recording, vehicle ........................... 9-2
Diagnostic connector .............................. 9-2
Dimmer switch ...................................... 3-14
D-mode (drive mode) ............................ 3-13
Drive chain, cleaning and lubricating .... 6-24 Drive chain slack .................................. 6-22
EEngine break-in ...................................... 5-3
Engine idling speed, checking .............. 6-14
Engine oil .............................................. 6-10
Engine serial number.............................. 9-1
Engine trouble warning light ................... 3-5FFront and rear brake
pads, checking .... 6-20
Front fork, adjusting .............................. 3-24
Front fork, checking .............................. 6-27
Fuel....................................................... 3-20
Fuel consumption, tips for reducing........ 5-3
Fuel tank cap ........................................ 3-19
Fuel tank overflow hose and breather hose ................................................... 3-22
Fuses, replacing ................................... 6-30HHandlebar switches .............................. 3-14
Hazard switch ....................................... 3-15
Headlight bulb, replacing ...................... 6-32
High beam indicator light ........................ 3-4
Horn switch ........................................... 3-14IIdentification numbers ............................ 9-1
Ignition circuit cut-off system ................ 3-28
Immobilizer system ................................. 3-1
Immobilizer system indicator light........... 3-5
Indicator lights and warning lights .......... 3-4LLicense plate light ................................. 6-35
Luggage strap holders .......................... 3-27MMain switch/steering lock........................ 3-2 Maintenance and lubrication, periodic..... 6-5
Maintenance, emission control system ... 6-3
Matte color, caution ................................. 7-1
Model label .............................................. 9-2
Multi-function meter unit .......................... 3-6
NNeutral indicator light .............................. 3-4OOil level warning light .............................. 3-4PParking .................................................... 5-4
Part locations .......................................... 2-1
Pass switch ........................................... 3-14SSafety information ................................... 1-1
Seat ....................................................... 3-23
Shifting .................................................... 5-2
Shift pedal ............................................. 3-16
Shock absorber assembly, adjusting .... 3-25
Sidestand .............................................. 3-27
Sidestand, checking an
d lubricating...... 6-26
Spark plugs, checking ............................. 6-9
Specifications .......................................... 8-1
Starting the engine .................................. 5-1
Steering, checking................................. 6-28
Stop/Run/Start switch............................ 3-15
Storage.................................................... 7-3
Storage compartment............................ 3-23
Supporting the motorcycle .................... 6-36
Swingarm pivots, lubricating ................. 6-27TThrottle grip and cable, checking and lubricating ........................................... 6-25
Throttle grip free play, checking ............ 6-15
UB90E2.book 1 ページ 2018年6月5日 火曜日 午後5時40分