2010 YAMAHA YZ85 check engine

TABLE OF CONTENTS
LOCATION OF IMPORTANT
LABELS ............................................1-1
SAFETY INFORMATION .................. 2-1
DESCRIPTION .................................. 3-1
Left view .......................................... 3-1
Right view ........................................ 3-2
Controls and instruments ................3-3
INSTRUMENT AND CONTROL
FUNCTIONS....................................... 4-1
Handlebar switch ............................ 4-1
Clutch lever .................................... 4-1
Shift pedal ......................................4-1
Brake lever ..................................... 4-2
Brake pedal .................................... 4-2
Fuel tank cap .................................. 4-3
Fuel ................................................ 4-3
Fuel tank breather hose ................. 4-5
Fuel cock ........................................ 4-5
Starter (choke) knob ....................... 4-6
Kickstarter ......................................4-6
Seat ................................................ 4-7
Adjusting the front fork ................... 4-7
Front fork bleeding ......................... 4-9
Adjusting the shock absorber
assembly ..................................... 4-9
Removable sidestand ................... 4-12FOR YOUR SAFETY –
PRE-OPERATION CHECKS............. 5-1
OPERATION AND IMPORTANT
RIDING POINTS................................ 6-1
Starting and warming up a cold
engine ......................................... 6-1
Starting a warm engine .................. 6-1
Shifting ........................................... 6-2
Engine break-in .............................. 6-3
Parking ........................................... 6-4
PERIODIC MAINTENANCE AND
ADJUSTMENT................................... 7-1
Periodic maintenance and
lubrication chart .......................... 7-2
Checking the spark plug ................ 7-8
Transmission oil ............................. 7-9
Coolant ........................................ 7-10
Cleaning the air filter element ...... 7-12
Adjusting the carburetor ............... 7-14
Adjusting the engine idling
speed ........................................ 7-14
Adjusting the throttle cable free
play ........................................... 7-14
Tires ............................................. 7-15
Spoke wheels .............................. 7-17
Adjusting the clutch lever free
play ........................................... 7-17
Checking the front brake lever
free play .................................... 7-18Checking the shift pedal ............... 7-19
Checking the front and rear brake
pads .......................................... 7-19
Checking the brake fluid level ...... 7-20
Changing the brake fluid .............. 7-21
Drive chain slack .......................... 7-21
Cleaning and lubricating the drive
chain ......................................... 7-22
Checking and lubricating
the cables ................................. 7-23
Checking and lubricating
the throttle grip and cable ......... 7-23
Checking and lubricating
the brake and clutch levers ....... 7-23
Checking and lubricating
the brake pedal ......................... 7-24
Lubricating the swingarm pivots ... 7-24
Lubricating the rear suspension ... 7-25
Checking the front fork ................. 7-25
Checking the steering .................. 7-26
Checking the wheel bearings ....... 7-26
Supporting the motorcycle ........... 7-26
Front wheel .................................. 7-27
Rear wheel ................................... 7-28
Troubleshooting ........................... 7-29
Troubleshooting charts ................. 7-31
MOTORCYCLE CARE AND
STORAGE.......................................... 8-1
Matte color caution ......................... 8-1
Care ............................................... 8-1
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INSTRUMENT AND CONTROL FUNCTIONS
4-5
4wash with soap and water. If gaso-
line spills on your clothing, change
your clothes.
EAU41360
Fuel tank breather hose Before operating the motorcycle:

Check the fuel tank breather hose
connection.


Check the fuel tank breather hose
for cracks or damage, and replace
it if damaged.


Make sure that the end of the fuel
tank breather hose is not blocked,
and clean it if necessary.
TIPIf the fuel tank breather hose falls out,
reinstall it on the fuel tank cap with the
arrow mark on the one-way valve point-
ed downward as shown.
EAU41280
Fuel cock The fuel cock supplies fuel from the
tank to the carburetor while filtering it al-
so.
The fuel cock has two positions:
OFF
With the lever in this position, fuel will
not flow. Always return the lever to this
position when the engine is not running.
1. Fuel tank breather hose
2. One-way valve
1. Arrow mark positioned over “OFF”
U5PA88E0.book Page 5 Tuesday, June 9, 2009 8:44 AM

OPERATION AND IMPORTANT RIDING POINTS
6-3
6
EAU41503
Engine break-in
WARNING
EWA10321
Failure to properly maintain the ve-
hicle or performing maintenance ac-
tivities incorrectly may increase
your risk of injury or death during
service or while using the vehicle. If
you are not familiar with vehicle ser-
vice, have a Yamaha dealer perform
service.1. Before starting the engine, fill the
fuel tank with a break-in oil-fuel
mixture as follows.
2. Start and warm up the engine.
Check the operation of the controls
and the engine stop button. (See
page 4-1.)
3. Operate the motorcycle in the low-
er gears at moderate throttle open-
ings for five to eight minutes. Stop
the engine and check the sparkplug condition (see page 7-8); it
will show a rich condition during
break-in.
4. Allow the engine to cool. Restart
the engine and operate the motor-
cycle as in the step above for five
minutes. Then, very briefly shift to
the higher gears and check the
full-throttle response. Stop the en-
gine and check the spark plug.
5. After again allowing the engine to
cool, restart and run the motorcy-
cle for five more minutes. Full
throttle and the higher gears may
be used, but sustained full-throttle
operation should be avoided. Stop
the engine and check the spark
plug again.
6. Allow the engine to cool, remove
the cylinder head and cylinder, and
inspect the piston and cylinder.
Remove any high spots on the pis-
ton with #600-grit wet sandpaper.
Clean all components and careful-
ly reassemble the cylinder head
and cylinder.
7. Drain the break-in oil-fuel mixture
from the fuel tank and refill with the
specified mix. (See page 4-3.)8. Start the engine and check the op-
eration of the motorcycle through-
out its entire operating range. Stop
the engine and check the spark
plug condition. Restart the motor-
cycle and ride it for about 10 to 15
more minutes. The motorcycle will
now be ready to ride normally.
After the engine break-in period, thor-
oughly check the motorcycle for loose
parts, oil leakage and any other prob-
lems. Be sure to inspect and make ad-
justments thoroughly, especially cable
and drive chain slack and loose
spokes. In addition, check all fittings
and fasteners for looseness, and tight-
en if necessary.
NOTICE
ECA15560


When any of the following parts
have been replaced, they must
be broken in.
Cylinder or crankshaft:
About one hour of break-in op-
eration is necessary.
Piston, rings or transmission
gears:
Recommended 2-stroke engine oil:
See page 9-1.
Mixing ratio (gasoline to oil):
15:1
U5PA88E0.book Page 3 Tuesday, June 9, 2009 8:44 AM

OPERATION AND IMPORTANT RIDING POINTS
6-4
6These parts require about 30
minutes of break-in operation at
half-throttle or less. Observe the
condition of the engine carefully
during operation.


If any engine trouble should oc-
cur during the engine break-in
period, immediately have a
Yamaha dealer check the vehi-
cle.
EAU17191
Parking When parking, stop the engine, and
then turn the fuel cock lever to “OFF”.
WARNING
EWA10311


Since the engine and exhaust
system can become very hot,
park in a place where pedestri-
ans or children are not likely to
touch them and be burned.


Do not park on a slope or on soft
ground, otherwise the vehicle
may overturn, increasing the
risk of a fuel leak and fire.


Do not park near grass or other
flammable materials which
might catch fire.
U5PA88E0.book Page 4 Tuesday, June 9, 2009 8:44 AM

PERIODIC MAINTENANCE AND ADJUSTMENT
7-8
7
EAU19613
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. Remove the spark plug cap.
2. Remove the spark plug as shown,
with a spark plug wrench available
at a Yamaha dealer.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).
TIPIf the spark plug shows a distinctly dif-
ferent color, the engine could be oper-
ating improperly. Do not attempt to
diagnose such problems yourself. In-
stead, 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
necessary.
3. Measure the spark plug gap with a
wire thickness gauge and, if nec-
essary, adjust the gap to specifica-
tion.
1. Spark plug cap
1. Spark plug wrench
Specified spark plug:
NGK/BR10EG1. Spark plug gapSpark plug gap:
0.5–0.6 mm (0.020–0.024 in)
U5PA88E0.book Page 8 Tuesday, June 9, 2009 8:44 AM

PERIODIC MAINTENANCE AND ADJUSTMENT
7-9
7 To install the spark plug
1. Clean the surface of the spark plug
gasket and its mating surface, and
then wipe off any grime from the
spark plug threads.
2. Install the spark plug with the
spark plug wrench, and then tight-
en it to the specified torque.
TIPIf a torque wrench is not available when
installing 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.3. Install the spark plug cap.
EAU41445
Transmission oil The transmission must be checked for
oil leakage before each ride. If any
leakage is found, have a Yamaha deal-
er check and repair the motorcycle. In
addition, the transmission oil must be
changed at the intervals specified in the
periodic maintenance and lubrication
chart.
1. Start the engine, warm it up for
several minutes, and then turn it
off.
2. Place the motorcycle on a level
surface and hold it in an upright po-
sition.
3. Place an oil pan under the trans-
mission to collect the used oil.
4. Remove the oil filler cap, the drain
bolt and the gasket to drain the oil
from the transmission.5. Install a new gasket and the trans-
mission oil drain bolt, and then
tighten the bolt to the specified
torque.
6. Refill with the specified amount of
the recommended transmission
oil, and then install and tighten the
oil filler cap.
Tightening torque:
Spark plug:
20 Nm (2.0 m·kgf, 14 ft·lbf)
1. Transmission oil filler cap
2. Transmission oil drain bolt
3. Gasket
Tightening torque:
Transmission oil drain bolt:
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
21
2
3
U5PA88E0.book Page 9 Tuesday, June 9, 2009 8:44 AM

PERIODIC MAINTENANCE AND ADJUSTMENT
7-10
7
NOTICE
ECA10452


In order to prevent clutch slip-
page (since the transmission oil
also lubricates the clutch), do
not mix any chemical additives.
Do not use oils with a diesel
specification of “CD” or oils of a
higher quality than specified. In
addition, do not use oils labeled
“ENERGY CONSERVING II” or
higher.


Make sure that no foreign mate-
rial enters the transmission.
7. Start the engine, and then let it idle
for several minutes while checking
the transmission for oil leakage. If
oil is leaking, immediately turn the
engine off and check for the cause.
EAU20070
Coolant The coolant level should be checked
before each ride. In addition, the cool-
ant must be changed at the intervals
specified in the periodic maintenance
and lubrication chart.
EAUM1294
To check the coolant level
1. Place the vehicle on a level sur-
face and hold it in an upright posi-
tion.
2. Remove the radiator cap and
check the coolant level in the radi-
ator. WARNING! Never attempt
to remove the radiator cap when
the engine is hot.
[EWA10381]
TIP

The coolant level must be checked
on a cold engine since the level
varies with engine temperature.


Make sure that the vehicle is posi-
tioned straight up when checking
the coolant level. A slight tilt to the
side can result in a false reading.
TIPThe coolant should be at the bottom of
the radiator filler neck. The level will
change with variation of engine temper-
ature.3. If the coolant is below this level,
add coolant, and then install the
radiator cap. NOTICE: If coolant
Recommended transmission oil:
See page 9-1.
Oil change quantity:
0.50 L (0.53 US qt, 0.44 Imp.qt)
1. Radiator cap
1. Correct coolant level
U5PA88E0.book Page 10 Tuesday, June 9, 2009 8:44 AM

PERIODIC MAINTENANCE AND ADJUSTMENT
7-11
7 is not available, use distilled wa-
ter or soft tap water instead. Do
not use hard water or salt water
since it is harmful to the engine.
If water has been used instead
of coolant, replace it with cool-
ant as soon as possible, other-
wise the cooling system will not
be protected against frost and
corrosion. If water has been
added to the coolant, have a
Yamaha dealer check the anti-
freeze content of the coolant as
soon as possible, otherwise the
effectiveness of the coolant will
be reduced.
[ECA10472]
EAUM1314
To change the coolant
1. Place the vehicle on a level sur-
face and let the engine cool if nec-
essary.
2. Place a container under the engine
to collect the used coolant.
3. Remove the coolant drain bolt and
the gasket, and then the radiator
cap to drain the cooling system.WARNING! Never attempt to re-
move the radiator cap when the
engine is hot.
[EWA10381]
4. After the coolant is completely
drained, thoroughly flush the cool-
ing system with clean tap water.5. Install a new gasket and the cool-
ant drain bolt, and then tighten the
bolt to the specified torque.
6. Pour the recommended coolant
into the radiator until it is full.
7. Install the radiator cap, start the
engine, let it idle for several min-
utes, and then turn it off.
8. Remove the radiator cap to check
the coolant level in the radiator. If
necessary, add sufficient coolant
until it reaches the bottom of the
radiator filler neck, and then install
the radiator cap.1. Coolant drain bolt
2. Gasket
1. Radiator cap
1
1
2
Tightening torque:
Coolant drain bolt:
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Antifreeze/water mixture ratio:
1:1
Recommended antifreeze:
High-quality ethylene glycol anti-
freeze containing corrosion inhibitors
for aluminum engines
Coolant quantity:
Radiator capacity (including all
routes):
0.54 L (0.57 US qt, 0.48 Imp.qt)
U5PA88E0.book Page 11 Tuesday, June 9, 2009 8:44 AM