compression ratio YAMAHA WR 250R 2009 Owners Manual

INSTRUMENT AND CONTROL FUNCTIONS
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EAU45262
Adjusting the shock absorber
assembly
This shock absorber assembly is
equipped with a spring preload adjust-
ing ring, a rebound damping force ad-
justing dial and a compression
damping force adjusting screw.
NOTICE

ECA10101
To avoid damaging the mechanism,
do not attempt to turn beyond the
maximum or minimum settings.
Spring preload
Spring preload adjustment should be
made by a Yamaha dealer, since this
service requires special tools and tech-
nical skills. The specified settings are
listed below.
The spring preload setting is deter-
mined by measuring distance A, shown
in the illustration. The shorter the dis-
tance A is, the higher the spring pre-
load; the longer distance A is, the lower
the spring preload.
Rebound damping force
To increase the rebound damping force
and thereby harden the rebound damp-
ing, turn the adjusting dial in direction
(a). To decrease the rebound damping
force and thereby soften the rebound
damping, turn the adjusting dial in di-
rection (b).
Compression damping force
To increase the compression damping
force and thereby harden the compres-
sion damping, turn the adjusting screw
in direction (a). To decrease the com-
pression damping force and thereby
soften the compression damping, turn

1. Distance A
Spring preload:
Minimum (soft):
Distance A = 216 mm (8.50 in)
Standard:
Distance A = 211.5 mm (8.33 in)
Maximum (hard):
Distance A = 206 mm (8.11 in)
1
1. Rebound damping force adjusting dial
Rebound damping setting:
Minimum (soft):
25 click(s) in direction (b)*
Standard:
12 click(s) in direction (b)*
Maximum (hard):
3 click(s) in direction (b)*
* With the adjusting dial fully turned in
direction (a)
(a) (b) 1

PERIODIC MAINTENANCE AND ADJUSTMENT
6-39
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6. Push the wheel forward, and then
remove the drive chain from the
rear sprocket.
TIP

The drive chain does not need to be
disassembled in order to remove and
install the rear wheel.
7. Remove the wheel.
NOTICE:
Do
not apply the brake after the
wheel has been removed to-
gether with the brake disc, oth-
erwise the brake pads will be
forced shut.
[ECA11071]

EAU45190
To install the rear wheel
1. Install the wheel and the brake cal-
iper bracket by inserting the wheel
axle from the left-hand side.
TIP


Make sure that the retainer on the
brake caliper bracket is inserted
into the slot in the swingarm.

Make sure that there is enough
space between the brake pads be-
fore installing the wheel.2. Install the drive chain onto the rear
sprocket.
3. Install the washer and the axle nut,
and then lower the rear wheel so
that it is on the ground.
4. Adjust the drive chain slack. (See
page 6-25.)
5. Tighten the axle nut to the speci-
fied torque.
EAU25871
Troubleshooting
Although Yamaha motorcycles receive
a thorough inspection before shipment
from the factory, trouble may occur dur-
ing 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 inferi-
or, have a shorter service life and can
lead to expensive repair bills.
WARNING

EWA15141
When checking the fuel system, do
not smoke, and make sure there are
no open flames or sparks in the ar-
ea, including pilot lights from water
1. Brake caliper bracket
2. Retainer
3. Slot
Tightening torque:
Axle nut:
125 Nm (12.5 m·kgf, 90.4 ft·lbf)
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SPECIFICATIONS
EAU2633T

Dimensions:
Overall length:
2180 mm (85.8 in)
Overall width:
810 mm (31.9 in)
Overall height:
1230 mm (48.4 in)
Seat height:
930 mm (36.6 in)
Wheelbase:
1420 mm (55.9 in)
Ground clearance:
300 mm (11.81 in)
Minimum turning radius:
2300 mm (90.6 in)
Weight:
With oil and fuel:
134.0 kg (295 lb)
Engine:
Engine type:
Liquid cooled 4-stroke, DOHC
Cylinder arrangement:
Forward-inclined single cylinder
Displacement:
250.0 cm
3

Bore
×
stroke:
77.0
×
53.6 mm (3.03
×
2.11 in)
Compression ratio:
11.80 :1
Starting system:
Electric starter
Lubrication system:
Wet sump

Engine oil:
Type:
SAE 10W-30, SAE 10W-40, SAE 10W-50,
SAE 15W-40, SAE 20W-40 or SAE
20W-50
Recommended engine oil grade:
API service SG type or higher, JASO stan-
dard MA
Engine oil quantity:
Without oil filter element replacement:
1.30 L (1.37 US qt, 1.14 Imp.qt)
With oil filter element replacement:
1.40 L (1.48 US qt, 1.23 Imp.qt)
Cooling system:
Coolant reservoir capacity (up to the maxi-
mum level mark):
0.25 L (0.26 US qt, 0.22 Imp.qt)
Radiator capacity (including all routes):
0.90 L (0.95 US qt, 0.79 Imp.qt)
Air filter:
Air filter element:
Wet element
Fuel:
Recommended fuel:
Premium unleaded gasoline only
Fuel tank capacity:
7.6 L (2.01 US gal, 1.67 Imp.gal)
Fuel reserve amount:
2.1 L (0.55 US gal, 0.46 Imp.gal)
Fuel injection:
Throttle body:
Type/quantity:
38EIS/1
Spark plug (s):
Manufacturer/model:
NGK/CR9EK
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
Clutch:
Clutch type:
Wet, multiple-disc
Transmission:
Primary reduction system:
Spur gear
Primary reduction ratio:
78/25 (3.120)
Secondary reduction system:
Chain drive
Secondary reduction ratio:
43/13 (3.308)
Transmission type:
Constant mesh 6-speed
Operation:
Left foot operation
-20 -10 0
10 20 30
40
50 ˚C
SAE 10W-30
SAE 15W-40SAE 20W-40SAE 20W-50
SAE 10W-40SAE 10W-50