Yamaha Wr250r 2008 Manual

 
ENGINE 
3-9 
(Red/black ignition coil leads)
3. Check: 
 
Ignition timing

 
a. Start the engine, warm it up for several min-
utes, and then let it run at the specified en-
gine idling speed.
b. Check the firing range as shown.
Incorrect firing range  
→ 
 Check the ignition
system.
NOTE:
 
The ignition timing is not adjustable.

 
4. Remove: 
 
Timing light 
 
Digital tachometer
5. Install: 
 
Air scoop (left/right) 
 
Side cover...

 
ENGINE 
3-10 
7. Measure: 
 
Compression pressure
Out of specification  
→ 
 Refer to steps (c) and
(d).

 
a. Set the main switch to “ON”.
b. With the throttle wide open, crank the engine
until the reading on the compression gauge
stabilizes.
NOTE:
 
 
Make use the battery is fully charged when tak-
ing measurements. 
 
Make sure there is no compression leakage
from the connecting section of the compres- 
sion gauge.
c. If the compression pressure is above the...

 
ENGINE 
3-11
CAUTION:
 
 ECA13360 
 
Engine oil also lubricates the clutch and
the wrong oil types or additives could
cause clutch slippage. Therefore, do not
add any chemical additives or use engine
oils with a grade of CD or higher and do not
use oils labeled “ENERGY CONSERVING
II”. 
 
Do not allow foreign materials to enter the 
crankcase.
NOTE:
 
Before checking the engine oil level, wait a few 
minutes until the oil has settled.
4. Start the engine, warm it up for several min-
utes, and then...

 
ENGINE 
3-12 
ter element cover.

 
6. Check: 
 
Engine oil drain bolt gasket 
 
Oil filter element drain bolt gasket
Damage  
→ 
 Replace.
7. Install: 
 
Engine oil drain bolt
(along with the gasket)
8. Fill: 
 
Crankcase
(with the specified amount of the recom-
mended engine oil)
9. Install: 
 
Engine oil filler cap
10.Start the engine, warm it up for several min-
utes, and then turn it off.
11.Check: 
 
Engine
(for engine oil leaks)
12.Check: 
 
Engine oil...

 
ENGINE 
3-13 
obtained.
c. Tighten the locknut “1”.
NOTE:
 
If the specified clutch cable free play cannot be
obtained on the handlebar side of the cable, use 
the adjusting nut on the clutch cable side.

 
Clutch cable side 
a. Slide the clutch cable cover.
b. Loosen the locknuts “1”.
c. Turn the adjusting bolt “2” in direction “a” or
“b” until the specified clutch cable free play is
obtained.
d. Tighten the locknut “1”.
e. Return the clutch cable cover to its original...

 
ENGINE 
3-14 
9. Install: 
 
Air filter element frame
CAUTION:
 
 ECA14401 
Never operate the engine without the air filter
element installed. Unfiltered air will cause
rapid wear of engine parts and may damage
the engine. Operating the engine without the
air filter element will also affect carburetor
synchronization, leading to poor engine per- 
formance and possible overheating. 
10.Install: 
 
Air filter element assembly
11.Install: 
 
Air filter cover
12.Install: 
 
Side cover (right)
Refer to...

 
ENGINE 
3-15 
EAS21050 
CHECKING THE CYLINDER HEAD 
BREATHER HOSE 
1. Remove: 
 
Seat 
 
Side cover (left/right) 
 
Air scoop (left/right)
Refer to “GENERAL CHASSIS” on page 4-1. 
 
Fuel tank
Refer to “FUEL TANK” on page 7-1.
2. Check: 
 
Cylinder head breather hose “1”
Cracks/damage  
→ 
 Replace.
Loose connection  
→ 
 Connect properly.
CAUTION:
 
 ECA14920 
Make sure the cylinder head breather hose is 
routed correctly. 
3. Install: 
 
Fuel tank
Refer to “FUEL TANK” on page 7-1. 
 
Air scoop...

 
ENGINE 
3-16 
3. Check: 
 
EXUP system operation
NOTE:
 
Check operation by self-diagnostics diagnosis
mode No.“53”.
Refer to “FUEL INJECTION SYSTEM” on page 
8-29.
4. Check: 
 
EXUP cable free play (at the EXUP valve pul-
ley) 
 
Connect the battery power cables to the ser-
vo motor, and measure its play.
5. Adjust: 
 
EXUP cable free play
NOTE:
 
Install pulley cable 1 (black chrome plated) to
stamp 1 side, and install pulley cable 2 (white 
chrome plated) to stamp 2 side....

 
ENGINE 
3-17 
d. Insert the tailpipe into the muffler and align
the bolt holes.
e. Insert the bolt and tighten it.

 
EAS21090 
CHECKING THE CANISTER (FOR 
CALIFORNIA ONLY) 
1. Remove: 
 
Canister cover
Refer to “CANISTER (FOR CALIFORNIA)”
on page 7-13.
2. Check: 
 
Canister 
 
Hose
Cracks/damage  
→ 
 Replace.
3. Install: 
 
Canister cover 
EAS21110 
CHECKING THE COOLANT LEVEL 
1. Stand the vehicle on a level surface.
NOTE:
 
 
Place the vehicle on a suitable...

 
ENGINE 
3-18 
 
Radiator inlet hose “2” 
 
Radiator outlet hose “3”
Cracks/damage  
→ 
 Replace.
Refer to “RADIATOR” on page 6-1, “THER-
MOSTAT” on page 6-4 and “WATER PUMP”
on page 6-6.
3. Install: 
 
Fuel tank
Refer to “FUEL TANK” on page 7-1. 
 
Fuel tank (left/right) 
 
Seat
Refer to “GENERAL CHASSIS” on page 4-1. 
EAS21130 
CHANGING THE COOLANT 
1. Remove: 
 
Seat 
 
Air scoop (left/right)
Refer to “GENERAL CHASSIS” on page 4-1.
2. Remove: 
 
Coolant reservoir hose “1” 
 
Recovery tank...