compression ratio YAMAHA YZ85 2015 Owners Manual

INSTRUMENT AND CONTROL FUNCTIONS
4-10
4
EAU41335
Adjustin g the shock a bsorb er
assem blyThis shock absorber assembly is
equipped with a spring preload adjust-
ing nut, a rebound damping force ad-
justing screw and a compression
damping force adjusting screw.NOTICE
ECA10102
To avoi d d amag ing the mechanism,
d o not attempt to turn b eyond the
maximum or minimum setting s.Spring preloa d
Adjust the spring preload as follows. 1. Loosen the locknut.
2. To increase the spring preload and thereby harden the suspen-
sion, turn the adjusting nut in di-
rection (a). To decrease the spring
preload and thereby soften the
suspension, turn the adjusting nut
in direction (b). 
A special wrench can be ob-
tained at a Yamaha dealer to
make this adjustment.
 The spring preload setting is
determined by measuring
distance A, shown in the illus-
tration. The longer distance A
is, the lower the spring pre-
load; the shorter distance A
is, the higher the spring pre-
load. With each complete
turn of the adjusting nut, dis-
tance A is changed by 1.5
mm (0.06 in). 3. Tighten the locknut to the speci-
fied torque. NOTICE: Always
ti g hten the locknut ag ainst the
a d justin g nut, an d then ti ghten
the locknut to the specified
torque.
[ECA10122]
1. Locknut
2. Spring preload adjusting nut
1. Distance ASprin g preloa d:
Minimum (soft): Distance A = 218.5 mm (8.60 in)
Standard:YZ85/YZ85F Distance A = 215.0 mm (8.46 in)
Standard:YZ85LW/YZ85LWF
Distance A = 207.0 mm (8.15 in)
For Europe only: Distance A =
212.0 mm (8.35 in)
Maximum (hard): Distance A = 202.5 mm (7.97 in)
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PERIODIC MAINTENANCE AND ADJUSTMENT
7-31
75. Adjust the drive chain slack. (See
page 7-22.)
6. Tighten the locknuts and the axle nut to their specified torques.
EAU25872
Trou bleshootin gAlthough Yamaha motorcycles receive
a thorough inspection before shipment
from the factory, trouble may occur
during operation. Any problem in the
fuel, compression, or ignition systems,
for example, can cause poor starting
and loss of power.
The following troubleshooting charts
represent quick and easy procedures
for checking these vital systems your-
self. However, should your motorcycle
require any repair, take it to a Yamaha
dealer, whose skilled technicians have
the necessary tools, experience, and
know-how to service the motorcycle
properly.
Use only genuine Yamaha replace-
ment parts. Imitation parts may look
like Yamaha parts, but they are often
inferior, have a shorter service life and
can lead to expensive repair bills.
WARNING
EWA15142
When checkin g the fuel system, do
not smoke, an d make sure there are
no open flames or sparks in the ar-
ea, inclu din g pilot lig hts from water heaters or furnaces. Gasoline or
g
asoline vapors can i gnite or ex-
plod e, causin g severe injury or prop-
erty damag e.
Tightenin g torque:
Locknut: 16 Nm (1.6 m·kgf, 12 ft·lbf)
Axle nut:
90 Nm (9.0 m·kgf, 65 ft·lbf)
U1SN83E0.book Page 31 Monday, September 8, 2014 2:36 PM

SPECIFICATIONS
9-1
9
Dimensions:Overall length:YZ85 1821 mm (71.7 in)
YZ85F 1821 mm (71.7 in)
YZ85LW 1899 mm (74.8 in)
YZ85LWF 1899 mm (74.8 in)
Overall width:
758 mm (29.8 in)
Overall height: YZ85 1126 mm (44.3 in)
YZ85F 1126 mm (44.3 in)
YZ85LW 1156 mm (45.5 in)
YZ85LWF 1156 mm (45.5 in)
Seat height: YZ85 841 mm (33.1 in)
YZ85F 841 mm (33.1 in)
YZ85LW 873 mm (34.4 in)
YZ85LWF 873 mm (34.4 in)
Wheelbase:
YZ85 1257 mm (49.5 in)
YZ85F 1257 mm (49.5 in)
YZ85LW 1285 mm (50.6 in)
YZ85LWF 1285 mm (50.6 in)
Ground clearance: YZ85 330 mm (12.99 in)
YZ85F 330 mm (12.99 in)
YZ85LW 360 mm (14.17 in)
YZ85LWF 360 mm (14.17 in)Wei ght:Curb weight:
YZ85 71 kg (157 lb)
YZ85F 71 kg (157 lb)
YZ85LW 73 kg (161 lb)
YZ85LWF 73 kg (161 lb)
Engine:Engine type:
Liquid cooled 2-stroke
Cylinder arrangement:
Single cylinder
Displacement: 85 cm³
Bore × stroke:
47.5 × 47.8 mm (1.87 × 1.88 in)
Compression ratio:
8.1 : 1
Starting system: Kickstarter
Lubrication system: PremixEngine oil:Type:
YAMALUBE 2RTransmission oil:Type:
YAMALUBE 4 (10W-40) or SAE 10W-40
Oil change quantity: 0.50 L (0.53 US qt, 0.44 Imp.qt)Coolant quantity:Radiator (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)
Car buretor:Type × quantity:
PWK28 x 1Spark plu g(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 ratio:
3.611 (65/18)
Final drive: Chain
Secondary reduction ratio: YZ85 3.428 (48/14)
YZ85F 3.428 (48/14)
YZ85LW 3.714 (52/14)
YZ85LWF 3.714 (52/14)
Transmission type:
Constant mesh 6-speed
Operation: Left foot operation
Gear ratio: 1st:2.454 (27/11)
2nd: 1.882 (32/17)
3rd:
1.529 (26/17)
4th: 1.294 (22/17)
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