2011 YAMAHA WR 250R compression ratio

INSTRUMENT AND CONTROL FUNCTIONS
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EAU45263
Adjusting the shock absorber
assembly This shock absorber assembly is
equipped with a spring preload adjust-
ing ring, a rebound damping force ad-
justing knob and a compression
damping force adjusting screw.NOTICE
ECA10101
To avoid damaging the mechanism,
do not attempt to turn beyond themaximum 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 knob in direction
(a). To decrease the rebound damping
force and thereby soften the rebound
damping, turn the adjusting knob 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
the adjusting screw in direction (b).
1. Distance ASpring preload:
Minimum (soft):
Distance A = 216.0 mm (8.50 in)
Standard:
Distance A = 211.5 mm (8.33 in)
Maximum (hard):
Distance A = 206.0 mm (8.11 in)
1
1. Rebound damping force adjusting knobRebound 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 knob fully turned in
direction (a)
(a) (b) 1
32D-9-E6.book 17 ページ ２０１１年１月７日　金曜日　午後３時１０分

PERIODIC MAINTENANCE AND ADJUSTMENT
6-41
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3
4
567
8
9 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.
4. Lower the rear wheel so that it is
on the ground, and then put the
sidestand down.
5. Adjust the drive chain slack. (See
page 6-27.)
6. Tighten the axle nut, and then the
locknuts to their specified torques.
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
1
2
3
Tightening torques:
Axle nut:
125 Nm (12.5 m·kgf, 90 ft·lbf)
Locknut:
16 Nm (1.6 m·kgf, 12 ft·lbf)
32D-9-E6.book 41 ページ ２０１１年１月７日　金曜日　午後３時１０分

8-1
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789
SPECIFICATIONS
EAU50912
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:Curb weight:
134 kg (295 lb)Engine:Engine type:
Liquid cooled 4-stroke, DOHC
Cylinder arrangement:
Single cylinder
Displacement:
250 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:Recommended brand:
YAMALUBE
Type:
SAE 10W-30, 10W-40, 10W-50, 15W-40,
20W-40 or 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:
ID mark:
3D71 10Spark plug(s):Manufacturer/model:
NGK/CR9EK
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)Clutch:Clutch type:
Wet, multiple-discTransmission:Primary reduction ratio:
3.120 (78/25)
Final drive:
Chain
Secondary reduction ratio:
3.308 (43/13)
Transmission type:
Constant mesh 6-speed
Operation:
Left foot operation
–20 –10 0
1020 30 40 50 C 10 30 50 70 90 110 0 130 F
SAE 10W-30
SAE 15W-40SAE 20W-40SAE 20W-50
SAE 10W-40SAE 10W-50
32D-9-E6.book 1 ページ ２０１１年１月７日　金曜日　午後３時１０分