INSTRUMENT AND CONTROL FUNCTIONS
4-6
4 ON
With the lever in this position, fuel flows
to the carburetor. Normal riding is done
with the lever in this position.
EAU13640
Starter (choke) knob Starting a cold engine requires a richer
air-fuel mixture, which is supplied by
the starter (choke).
Move the knob in direction (a) to turn on
the starter (choke).
Move the knob in direction (b) to turn off
the starter (choke).
EAU13650
Kickstarter To start the engine, fold out the kick-
starter lever, move it down lightly with
your foot until the gears engage, and
then push it down smoothly but force-
fully. This model is equipped with a pri-
mary kickstarter, allowing the engine to
be started in any gear if the clutch is
disengaged. However, shifting the
transmission into the neutral position
before starting is recommended.
1. Arrow mark positioned over “ON”
1. Starter (choke) knob
1. Kickstarter lever
U5PA88E0.book Page 6 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
PERIODIC MAINTENANCE AND ADJUSTMENT
7-16
7
Be sure the valve stem is posi-
tioned straight. A tilted valve
stem indicates that the tire has
slipped from its original posi-
tion on the rim. Rotate the tire
so that the valve stem is posi-
tioned straight.
If the center tread depth reaches the
specified limit, if the tire has a nail or
glass fragments in it, or if the sidewall is
cracked, have a Yamaha dealer re-
place the tire immediately.
Tire information
This motorcycle is equipped with spoke
wheels and tube tires.
WARNING
EWA10461
The front and rear tires should be of
the same make and design, other-
wise the handling characteristics of
the vehicle may be different, which
could lead to an accident.
After extensive tests, only the tires list-
ed below have been approved for this
model by Yamaha Motor Co., Ltd.
WARNING
EWA14390
Have a Yamaha dealer replace
excessively worn tires. Operat-
ing the motorcycle with exces-
sively worn tires decreases
riding stability and can lead to
loss of control.
The replacement of all wheel-
and brake-related parts, includ-
ing the tires, should be left to a
Yamaha dealer, who has the
necessary professional knowl-
edge and experience.
It is not recommended to patch
a punctured tube. If unavoid-
able, however, patch the tube
very carefully and replace it as
soon as possible with a high-
quality product.
Minimum tire tread depth (front and
rear):
4.0 mm (0.16 in)
Front tire:
Size:
YZ85 70/100-17 40M
YZ85LW 70/100-19 42M
YZ85LWZ 70/100-19 42M
YZ85Z 70/100-17 40M
Manufacturer/model:
YZ85 DUNLOP/D739FA (ZAF)
YZ85 DUNLOP/D756F
(AUT)(BEL)(CHE)(DEU)(DNK)(ES
P)(FIN)(FRA)(GBR)(GRC)(IRL)(IT
A)(NLD)(NOR)(POL)(PRT)(SVN)(
SWE)
YZ85LW DUNLOP/D739FA (ZAF)
YZ85LW DUNLOP/D756F
(AUT)(BEL)(CHE)(DEU)(DNK)(ES
P)(FIN)(FRA)(GBR)(GRC)(IRL)(IT
A)(NLD)(NOR)(POL)(PRT)(SVN)(
SWE)
YZ85LWZ DUNLOP/D756F
YZ85Z DUNLOP/D756F
Rear tire:
Size:
YZ85 90/100-14 49M
YZ85LW 90/100-16 52M
YZ85LWZ 90/100-16 52M
YZ85Z 90/100-14 49M
Manufacturer/model:
DUNLOP/D756
U5PA88E0.book Page 16 Tuesday, June 9, 2009 8:44 AM
SPECIFICATIONS
9-1
9
Dimensions:Overall length:
YZ85 1818 mm (71.6 in)
(AUT)(BEL)(CHE)(DEU)(DNK)(ESP)(FIN)
(FRA)(GBR)(GRC)(IRL)(ITA)(NLD)(NOR)
(POL)(PRT)(SVN)(SWE)
YZ85 1821 mm (71.7 in) (ZAF)
YZ85LW 1903 mm (74.9 in)
YZ85LWZ 1903 mm (74.9 in)
YZ85Z 1818 mm (71.6 in)
Overall width:
758 mm (29.8 in)
Overall height:
YZ85 1161 mm (45.7 in)
YZ85LW 1205 mm (47.4 in)
YZ85LWZ 1205 mm (47.4 in)
YZ85Z 1161 mm (45.7 in)
Seat height:
YZ85 864 mm (34.0 in)
YZ85LW 904 mm (35.6 in)
YZ85LWZ 904 mm (35.6 in)
YZ85Z 864 mm (34.0 in)
Wheelbase:
YZ85 1255 mm (49.4 in)
(AUT)(BEL)(CHE)(DEU)(DNK)(ESP)(FIN)
(FRA)(GBR)(GRC)(IRL)(ITA)(NLD)(NOR)
(POL)(PRT)(SVN)(SWE)
YZ85 1258 mm (49.5 in) (ZAF)
YZ85LW 1286 mm (50.6 in)
YZ85LWZ 1286 mm (50.6 in)
YZ85Z 1255 mm (49.4 in)Ground clearance:
YZ85 351 mm (13.82 in)
YZ85LW 393 mm (15.47 in)
YZ85LWZ 393 mm (15.47 in)
YZ85Z 351 mm (13.82 in)
Weight:With oil and fuel:
YZ85 71.0 kg (157 lb)
YZ85LW 73.9 kg (163 lb)
YZ85LWZ 73.9 kg (163 lb)
YZ85Z 71.0 kg (157 lb)Engine:Engine type:
Liquid cooled 2-stroke
Cylinder arrangement:
Forward-inclined single cylinder
Displacement:
84 cm³
Bore × stroke:
47.5 × 47.8 mm (1.87 × 1.88 in)
Compression ratio:
8.20 :1
Starting system:
Kickstarter
Lubrication system:
PremixEngine oil:Type:
YAMALUBE 2-RTransmission oil:Type:
YAMALUBE 4 (10W-40) or SAE 10W-40
Oil change quantity:
0.50 L (0.53 US qt, 0.44 Imp.qt)
Cooling system:Radiator capacity (including all routes):
0.54 L (0.57 US qt, 0.48 Imp.qt)Air filter:Air filter element:
Wet elementFuel:Recommended fuel:
Premium unleaded gasoline only
Fuel tank capacity:
5.0 L (1.32 US gal, 1.10 Imp.gal)Carburetor:Type × quantity:
PWK28 x 1Spark plug (s):Manufacturer/model:
NGK/BR10EG
Spark plug gap:
0.5–0.6 mm (0.020–0.024 in)Clutch:Clutch type:
Wet, multiple-discTransmission:Primary reduction system:
Spur gear
Primary reduction ratio:
65/18 (3.611)
Secondary reduction system:
Chain drive
U5PA88E0.book Page 1 Tuesday, June 9, 2009 8:44 AM
SPECIFICATIONS
9-2
9
Secondary reduction ratio:
YZ85 47/14 (3.357) (ZAF)
YZ85 48/14 (3.428)
(AUT)(BEL)(CHE)(DEU)(DNK)(ESP)(FIN)
(FRA)(GBR)(GRC)(IRL)(ITA)(NLD)(NOR)
(POL)(PRT)(SVN)(SWE)
YZ85LW 52/14 (3.714)
YZ85LWZ 52/14 (3.714)
YZ85Z 48/14 (3.428)
Transmission type:
Constant mesh 6-speed
Operation:
Left foot operation
Gear ratio:
1st:
27/11 (2.454)
2nd:
32/17 (1.882)
3rd:
26/17 (1.529)
4th:
22/17 (1.294)
5th:
26/23 (1.130)
6th:
25/25 (1.000)Chassis:Frame type:
Semi double cradle
Caster angle:
YZ85 26.30 °
YZ85LW 27.00 °
YZ85LWZ 27.00 °
YZ85Z 26.30 °Trail:
YZ85 88.0 mm (3.46 in)
YZ85LW 106.0 mm (4.17 in)
YZ85LWZ 106.0 mm (4.17 in)
YZ85Z 88.0 mm (3.46 in)
Front tire:Type:
With tube
Size:
YZ85 70/100-17 40M
YZ85LW 70/100-19 42M
YZ85LWZ 70/100-19 42M
YZ85Z 70/100-17 40M
Manufacturer/model:
YZ85 DUNLOP/D739FA (ZAF)
YZ85 DUNLOP/D756F
(AUT)(BEL)(CHE)(DEU)(DNK)(ESP)(FIN)
(FRA)(GBR)(GRC)(IRL)(ITA)(NLD)(NOR)
(POL)(PRT)(SVN)(SWE)
YZ85LW DUNLOP/D739FA (ZAF)
YZ85LW DUNLOP/D756F
(AUT)(BEL)(CHE)(DEU)(DNK)(ESP)(FIN)
(FRA)(GBR)(GRC)(IRL)(ITA)(NLD)(NOR)
(POL)(PRT)(SVN)(SWE)
YZ85LWZ DUNLOP/D756F
YZ85Z DUNLOP/D756FRear tire:Type:
With tube
Size:
YZ85 90/100-14 49M
YZ85LW 90/100-16 52M
YZ85LWZ 90/100-16 52M
YZ85Z 90/100-14 49MManufacturer/model:
DUNLOP/D756
Tire air pressure (measured on cold
tires):
Front:
100 kPa (1.00 kgf/cm², 15 psi)
Rear:
100 kPa (1.00 kgf/cm², 15 psi)
Front wheel:Wheel type:
Spoke wheel
Rim size:
YZ85 17x1.40
YZ85LW 19x1.40
YZ85LWZ 19x1.40
YZ85Z 17x1.40Rear wheel:Wheel type:
Spoke wheel
Rim size:
YZ85 14x1.60
YZ85LW 16x1.85
YZ85LWZ 16x1.85
YZ85Z 14x1.60Front brake:Type:
Single disc brake
Operation:
Right hand operation
Recommended fluid:
DOT 4Rear brake:Type:
Single disc brake
U5PA88E0.book Page 2 Tuesday, June 9, 2009 8:44 AM
CONSUMER INFORMATION
10-1
10
EAU40791
Identification numbers Record the vehicle identification num-
ber and model label information in the
spaces provided below for assistance
when ordering spare parts from a
Yamaha dealer or for reference in case
the vehicle is stolen.
VEHICLE IDENTIFICATION
NUMBER:
MODEL LABEL INFORMATION:
EAU26400
Vehicle identification number
The vehicle identification number is
stamped into the steering head pipe.
Record this number in the space pro-
vided.TIPThe vehicle identification number is
used to identify your motorcycle and
may be used to register your motorcy-
cle with the licensing authority in your
area.
EAU26460
Model label
The model label is affixed to the loca-
tion shown. Record the information on
this label in the space provided. This in-
formation will be needed when ordering
spare parts from a Yamaha dealer.
1. Vehicle identification number
1. Model label
U5PA88E0.book Page 1 Tuesday, June 9, 2009 8:44 AM