Honda Crf250l Service Manual

							14-10
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CRANKCASE/CRANKSHAFT/TRANSMISSION/BALANCER
Press the bearings [1] until the metal installer flange [2]
is fully seated.
Make sure the bearing mating line is aligned with the
index mark on the crankcase.
Check the oil clearance (page 14-7).
After selecting new bearings, recheck the oil clearance.
Incorrect clearance can cause severe engine damage.
Install the following:
– Crankshaft (page 14-6)
– Transmission (page 14-11)
– Balancer shaft (page 14-14)
TRANSMISSION
REMOVAL/DISASSEMBLY
Separate the crankcase halves (page 14-4).
Pull the shift fork shaft [1] and remove it from the shift
forks.
Remove the shift forks [2] and shift drum [3].
Remove the mainshaft assembly [1] and countershaft
assembly [2] together.
[1]
[2]
Align
[1][2]
[3]
[1]
[2] 
						

							14-11
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CRANKCASE/CRANKSHAFT/TRANSMISSION/BALANCER
Disassemble the mainshaft assembly [1] and
countershaft assembly [2].
 • Keep track of the disassembled parts (gears,
bushings, washers, and snap rings) by sliding them
onto a tool or a piece of wire.
 • Do not expand the snap ring more than necessary
for removal. To remove a snap ring, expand the
snap ring and pull it off using the gear behind it.
INSPECTION
Inspect the following parts for scratch, damage,
abnormal wear and deformation. Replace if necessary.
– Transmission gears
– Transmission bushings
– Transmission bearings
– Shift drum/journal
– Shift forks
– Shift fork shaft
Measure each part and calculate the clearance
according to CRANKC ASE/CRANKSHAFT/TRANS-
MISSION/BALANCER SPECIFICATIONS (page 1-7).
Replace any part if it is out of service limit.
ASSEMBLY/INSTALLATION
Clean all parts in solvent, and dry them thoroughly.
Apply molybdenum oil solution to the gear bushing
entire surface (M5, C1, C2, C3), gear bushing outer
surface (M6, C4) to ensure initial lubrication.
Assemble all parts into their original positions.
 • Install the washers and snap rings [1] with the chamfered edge facing the th rust load side. Confirm
the inner side of snap rings and washer when you
detect the chamfered side.
 • Do not reuse worn snap ring which could easily spin
in the groove.
 • Check that the snap rings are seated in the grooves and align their end gaps with the grooves of the
spline.
[1]
[2]
CORRECTINCORRECT
[1] 
						

							14-12
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CRANKCASE/CRANKSHAFT/TRANSMISSION/BALANCER
MAINSHAFT
COUNTERSHAFT
THRUST WASHER
M5 GEAR (26T)
M6 GEAR (27T)
M3/M4 GEAR (21/23T)
SPLINE WASHER
M6 GEAR BUSHING
SPLINE WASHER
M5 GEAR BUSHING
WASHER
M2 GEAR (17T)
SNAP RING
THRUST WASHER
SNAP RING
MAINSHAFT/ M1 GEAR (12T)
THRUST WASHERC1 GEAR (40T)
C1 GEAR BUSHING
SNAP RING
THRUST WASHER
C5 GEAR (29T)
SPLINE WASHER
C4 GEAR (30T)
THRUST WASHER
C2 GEAR (36T)
C2 GEAR BUSHING
C6 GEAR (26T)
THRUST WASHER
COUNTERSHAFT
C3 GEAR BUSHING
C3 GEAR (33T)
LOCK WASHER
C4 GEAR BUSHING
SPLINE 
WASHER
WASHER 
						

							14-13
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CRANKCASE/CRANKSHAFT/TRANSMISSION/BALANCER
Check the gears for freedom of movement or rotation
on each shaft.
Apply engine oil to the transmission gear teeth.
Engage the mainshaft assembly [1] and countershaft
assembly [2].
Install the mainshaft assembly [1] and countershaft
assembly [2] together into the right crankcase.
Make sure the three thrust washers are installed
(mainshaft; left only/countershaft; both ends).
Each shift fork has an identification marks [1], R is for
the right shift fork, L is the left shift fork and C is for
the center shift fork.
Apply molybdenum oil solution to the shift fork inner
surfaces and guide pins.
Install the shift forks [1] into the shifter gear grooves
with the identification marks facing up (left crankcase
side).
Apply molybdenum oil solution to the shift drum [2]
journal outer surface and grooves, then install it while
aligning the shift fork guide pins with the guide grooves.[1]
[2]
: Each gear teeth
[1]
[2]
[1]
[1]
[2] 
						

							14-14
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CRANKCASE/CRANKSHAFT/TRANSMISSION/BALANCER
Apply molybdenum oil solution to the shift fork shaft [1]
outer surface and insert it through the shift forks into the
right crankcase.
After installation, check for smooth transmission
operation.
Assemble the crankcase (page 14-18).
BALANCER
BALANCER SHAFT REMOVAL/
INSTALLATION
Separate the crankcase halves (page 14-4).
Remove the balancer shaft [1] from the right crankcase.
Install the balancer shaft into the right crankcase.
Assemble the crankcase (page 14-18).
BALANCER DRIVEN GEAR 
DISASSEMBLY/ASSEMBLY
Disassemble and assemble the balancer driven gear as following illustration.
[1]
[1]
SPRINGS
OUT MARK
SNAP RING
WASHER
SPRING WASHER
WASHER
BALANCER DRIVEN 
SUB GEAR
BALANCER 
DRIVEN GEAR
Align
SNAP RING
WASHER
SPRING WASHERWASHERBALANCER DRIVEN SUB GEAR
BALANCER 
DRIVEN GEAR 
						

							14-15
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CRANKCASE/CRANKSHAFT/TRANSMISSION/BALANCER
INSPECTION
Inspect the following parts for scratch, damage,
abnormal wear and deformation. Replace if necessary.
– Balancer driven gear
– Balancer driven sub gear
–Springs
– Balancer shaft
– Balancer drive gear
CRANKCASE BEARING 
REPLACEMENT
BALANCER/TRANSMI SSION BEARING
Remove the following:
– Crankshaft (page 14-6)
– Balancer shaft (page 14-14)
– Transmission (page 14-10)
RIGHT CRANKCASE SIDE
Remove the bolts [1] and mainshaft bearing setting
plate [2].
Drive out the mainshaft bearing [3], shift drum bearing
[4] and balancer shaft bearing [5].
Remove the countershaft bearing [1] using the special
tools.
[3][5][2]
[1][4]
TOOLS:
[2] Bearing remover set, 17 mm 07936-3710300
Remover handle 07936-3710100
[3] Remover weight 07741-0010201
[1]
[2][3] 
						

							14-16
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CRANKCASE/CRANKSHAFT/TRANSMISSION/BALANCER
Drive in new bearings into the right crankcase until they
are fully seated using the special tools.
After installation, apply engine oil to each bearing
rotating area.
Drive in a new balancer shaft bearing into the right
crankcase until it is fully seated using the special tools.
After installation, apply engine oil to the bearing rotating
area.
Apply locking agent to the mainshaft bearing setting
plate bolt [1] threads (page 1-15).
Install the setting plate [2] with its OUTSIDE mark [3]
facing out.
Install and tighten the bolts securely.
LEFT CRANKCASE SIDE
Remove the snap ring [1].
Remove the countershaft oil seal [2] from the left
crankcase. TOOLS:
[1] Mainshaft bearing (m arked side facing up):
[2] Driver 07749-0010000
[3] Attachment, 52 x 55 mm 07746-0010400
[4] Pilot, 20 mm 07746-0040500
[5] Countershaft bearing (s ealed side facing down):
Driver 07749-0010000
Attachment, 37 x 40 mm 07746-0010200
Pilot, 17 mm 07746-0040400
[6] Shift drum bearing (m arked side facing up):
Driver 07749-0010000
Attachment, 42 x 47 mm 07746-0010300[2][2][3]/[4]
[5]
[6][1]
TOOLS:
[1] Balancer shaft bearing  (marked side facing up):
[2] Driver 07749-0010000
[3] Attachment, 42 x 47 mm 07746-0010300
[4] Pilot, 20 mm 07746-0040500
[2][2][3]/[4]
[1]
[1][2]
[3]
[2]
[1] 
						

							14-17
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CRANKCASE/CRANKSHAFT/TRANSMISSION/BALANCER
Drive out the countershaft bearing [1].
Remove the mainshaft needle bearing [1] using the
special tools.
Remove the balancer shaft bearing [1] using the special
tools.
Drive in new bearings into the left crankcase until they
are fully seated using the special tools.
After installation, apply engine oil to each bearing
rotating area.
[1]
TOOLS:
[2] Bearing remover set, 17 mm 07936-3710300
Remover handle 07936-3710100
[3] Remover weight 07741-0010201
[1]
[2][3]
TOOLS:
[2] Bearing remover set, 20 mm  07936-3710600
[3] Remover handle 07936-3710100
[4] Remover weight 07741-0010201
[2]
[1]
[3]
[4]
TOOLS:
[1] Mainshaft needle bearing:
[2] Driver 07749-0010000
[3] Attachment, 28 x 30 mm 07946-1870100
[4] Pilot, 17 mm 07746-0040400
[5] Countershaft bearing (marked side facing up): Driver 07749-0010000
Attachment, 52 x 55 mm 07746-0010400
Pilot, 22 mm 07746-0041000
[6] Balancer shaft bearing  (marked side facing up):
Driver 07749-0010000
Attachment, 42 x 47 mm 07746-0010300
Pilot, 20 mm 07746-0040500
[2]
[6]
[5]
[3]/[4]
[1] 
						

							14-18
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CRANKCASE/CRANKSHAFT/TRANSMISSION/BALANCER
Apply grease to a new countershaft oil seal [1] lips.
Install the countershaft oil seal with its marked side
facing up, until it is flush with the snap ring groove.
Install the snap ring [2].
CRANKCASE ASSEMBLY
Clean the oil passages of each crankcase using a
compressed air.
Check the oil passage for clogs.
Clean the left and right crankcase mating surfaces
thoroughly, being careful not to damage them and
check for damage.
Apply a light but through coating of sealant (Three bond
1207B, 1215 or equivalent) to left crankcase mating
surface except the oil passage area.
Apply engine oil to a new O-ring [1].
Install the dowel pins [2] and O-ring.
Make sure the snap
ring is firmly seated
in the groove.
[2]
[1]
[2]
[1]/[2] 
						

							14-19
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CRANKCASE/CRANKSHAFT/TRANSMISSION/BALANCER
Do not force the
crankcase halves
together, If there is excessive force
required, something
is wrong. Removethe left crankcase and check for
misaligned parts.Install the left crankcase [1] on the right crankcase [2],
being careful not to damage the oil seal lips.
Install the crankcase bolts [1].
Tighten the bolts in a crisscr oss pattern in 2 or 3 steps.
Be careful not to
damage the key
groove and
balancer shaft.Install the woodruff key [1] into the balancer shaft
groove.
Align the balancer gear [1] and balancer sub gear [2]
holes and install a 3 mm (0.12 in) pin [3] into the hole.
[2]
[1]
[1]
[1]
[2]
[1]
[3]