compression ratio YAMAHA YBR250 2007 Owners Manual

6-31
6
PERIODIC MAINTENANCE AND MINOR REPAIR
7. Push the wheel forward, and thenremove the drive chain from the
rear sprocket.The drive chain does not need to be
disassembled in order to remove and
install the wheel.8. Remove the wheel.
EAUW0170
To install the rear wheel1. Insert the wheel axle from the left- hand side, and then install the drive
chain onto the rear sprocket.
2. Install the axle nut.
3. Install the brake rod onto the brake camshaft lever, and then install the
brake pedal free play adjusting nut. 4. Connect the brake torque rod to the
brake shoe plate by installing the
bolt and the nut, and then tighten
the nut to the specified torque.
Tightening torque:Brake torque rod nut: 49 Nm (4.9 m.kgf, 36 ft.lbt)5. Adjust the drive chain slack. (See
page 6-19.)
6. Lower the rear wheel so that it is on the ground.
7. Tighten the axle nut to the specified torque.Tightening torque:Axle nut: 104 Nm (10.4 m.kgf, 77 ft.lbt)8. Adjust the brake pedal position and
free play. (See page 6-16)
EWA10660
After adjusting the brake pedal free
play, check the operation of the brake
light.
EAU25850
TroubleshootingAlthough 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 chart
represents a quick and easy procedure
for checking these vital systems
yourself. 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 replacement
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.
cap 6.pmd 24/1/2007, 14:38
31

8-1
SPECIFICATIONS
8
Dimensions:Overall length:2025 mm (79.7 in)
Overall width: 745 mm (29.3 in)
Overall height:
1065 mm (41.9 in)
Seat height:
805 mm (31.7 in)
Wheelbase: 1360 mm (53.5 in)
Ground clearance:
190 mm (7.5 in)
Minimum turning radius:
2395 mm (94.3 in)Weight:With oil and fuel:154.0 kg (339 lb)Engine:Engine type:Air cooled 4-stroke, SOHC
Cylinder arrangement: Forward-inclined single cylinder
Displacement:
249.0 cm
3 (15.2 cu.in)
Bore x stroke:
74.0 x 58.0 mm (2.91 x 2.28 in)
Compression ratio: 9.80:1
Starting system:
Electric starter
Lubrication system:
Wet sump
Engine oil:Type:SAE20W40 or SAE20W50Recommended engine oil grade: API service SF, SG type or higher
Engine oil quantity:
Without oil filter element replacement 1.35 L (1.43 US qt) (1.19 imp. qt)
With oil filter element replacement
1.45 L (1.53 US qt) (1.28 imp. qt)Air filter:Air filter element:Wet elementFuel:Recommended fuel:Regular unleaded gasoline only
Fuel tank capacity:
19.2 L (5.07 US gal) (4.22 imp. gal)
Fuel reserve amount:
4.5 L (1.19 US gal) (1.00 imp. gal)
Fuel injection:Manufacturer:AISAN
Model/quantity: 1100-87F70/1Spark plug:Manufacturer/model:NGK/DR8EA
Spark plug gap:
0.6-0.7 mm (0.024 - 0.028 in)Clutch:Clutch type:Wet, multiple-discTransmission:Primary reduction system:Spur gear
Primary reduction ratio:
74/24 (3.083)
Secondary reduction system: Chain drive
Secondary reduction ratio:
44/15 (2.933)
Transmission type:
Constant mesh 5-speed
Operation: Left foot operation
Gear ratio:
1st:
36/14 (2.571)
2nd:
32/19 (1.684)
3rd:
cap 8.pmd 24/1/2007, 14:38
1