Honda Crf250l Service Manual

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GENERAL INFORMATION
BRAKE/TAILLIGHT 6P 
(BLACK) CONNECTOR
LEFT REAR TURN SIGNAL 
2P (ORANGE) CONNECTORRIGHT REAR TURN 
SIGNAL 2P (LIGHT BLUE) 
CONNECTOR
MAIN WIRE HARNESS 
						

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GENERAL INFORMATION
EMISSION CONTROL SYSTEMS
SOURCE OF EMISSIONS
The combustion process produces carbon monoxide (CO), oxides of nitrogen (NOX) and hydrocarbons (HC). Control of oxides of
nitrogen and hydrocarbons is very important  because, under certain conditions, they react to form photochemical smog when
subject to sunlight. Carbon monoxide does not  react in the same way, but it is toxic.
Honda Motor Co., Ltd. utilizes various systems (page 1-28) to  reduce carbon monoxide, oxides of nitrogen and hydrocarbons.
CRANKCASE EMISSION CONTROL SYSTEM
The engine is equipped with a closed crankcase system to prevent discharging crankcase emissions  into the atmosphere. Blow-by
gas is returned to the combustion chamber through the air cleaner housing and throttle body.
BLOW-BY GAS
FRESH AIR
THROTTLE BODY
AIR CLEANER HOUSING
CRANKCASE 
BREATHER HOSE 
						

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GENERAL INFORMATIONEXHAUST EMISSION CONTROL SYSTEM
The exhaust emission control system is composed of a pulse seco ndary air supply system, three-way catalytic converter and PGM-
FI system.
SECONDARY AIR SUPPLY SYSTEM
The pulse secondary air supply system introduc es filtered air into the exhaust gases in the exhaust port. Fresh air is drawn in to the
exhaust port by the functi on of the PAIR control valve.
This charge of fresh air promotes burning  of the unburned exhaust gases and changes a  considerable amount of hydrocarbons and
carbon monoxide into relatively harmless carbon dioxide and water vapor.
The reed valve prevents reverse air flow through the system. The  PAIR control valve is operated by the solenoid valve. The
solenoid valve is controlled by the PGM-FI  unit, and the fresh air passage is opened/closed according to running condition (ECT /
IAT/TP/MAP sensor and engine revolution).
No adjustments to the secondary air supply system should  be made, although periodic inspection of the components is
recommended.
THREE-WAY CATALYTIC CONVERTER
This motorcycle is equipped with  a three-way catalytic converter.
The three-way catalytic converter is in the exhaust system. Throug h chemical reactions, it converts HC, CO and NO
X in the
engine’s exhaust to carbon dioxide (CO
2), nitrogen (N2), and water vapor.
No adjustment to these systems should be made although  periodic inspection of the components is recommended.
PAIR 
CHECK 
VALVE
EXHAUST PORT
FRESH AIR
EXHAUST GAS
PAIR CONTROL SOLENOID VALVEAIR CLEANER HOUSING
THROTTLE BODY 
						

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GENERAL INFORMATION
NOISE EMISSION CONTROL SYSTEM
TAMPERING WITH THE NOISE CONT ROL SYSTEM IS PROHIBITED: Local law may proh ibit the following acts or the causing
there of: (1) The removal or rendering inope rative by any person, other than for purposes of maintenance, repair or replacement, of
any device or element of design incorporated into any vehicle fo r the purpose of noise control prior to its sale or delivery to the
ultimate customer or while it is in use;  (2) the use of the vehicle after such device or element of design has been removed or
rendered inoperative by any person.
AMONG THOSE ACTS PRESUMED TO CONSTITUTE  TAMPERING ARE THE ACTS LISTED BELOW:
1. Removal of, or puncturing of the muffler, baffles, header  pipes or any other component which conducts exhaust gases.
2. Removal of, or puncturing of any part of the intake system.
3. Lack of proper maintenance.
4. Replacing any moving parts of the vehicle, or parts of the exhaust or intake system, with pa rts other than those specified by  the
manufacturer. 
						

							MEMO
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2
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2. FRAME/BODY PANELS/EXHAUST SYSTEM
SERVICE INFORMATION ·····························2-2
TROUBLESHOOTING···································2-2
SEAT······························································2-3
SIDE COVER ·················································2-3
RESERVE TANK COVER ···················\
··········2-4
FUEL TANK SHROUD ··································2-4
SKID PLATE ··················································2-5
HEADLIGHT COWL ······································2-5
FRONT FENDER ···········································2-5
FRAME GUARD ······ ··················\
··················\
··2-6 DRIVE SPROCKET COVER ························· 2-6
DRIVE CHAIN COVER 
(U TYPE ONLY)
··················\
··················\
········ 2-6
TOOL BOX ···················································· 2-7
REAR FENDER ············································· 2-7
REAR UPPER FENDER ······························· 2-8
TAIL COVER/LIGHT UNIT ···························· 2-8
REAR LOWER FENDER ······························ 2-9
EXHAUST PIPE/MU FFLER ··················\
······ 2-11
SUB-FRAME ··············································· 2-12
SIDESTAND ················································ 2-14 
						

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FRAME/BODY PANELS/EXHAUST SYSTEM
FRAME/BODY PANELS/EXHAUST SYSTEMSERVICE INFORMATION
GENERAL
 • This section covers removal and installation of the body panels, sub-frame and exhaust system.
 • Always replace the gaskets wh en removing the exhaust system.
 • Always inspect the exhaust system  for leaks after installation.
TROUBLESHOOTING
Excessive exhaust noise
 • Broken exhaust system
 • Exhaust gas leak
Poor performance
 • Deformed exhaust system
 • Exhaust gas leak
 • Clogged muffler 
						

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FRAME/BODY PANELS/EXHAUST SYSTEM
SEAT
REMOVAL/INSTALLATION
Remove the hook bolts [1] and collars [2].
Remove the seat [3] by pulling it rearward and releasing
the hooks.
Installation is in the reverse order of removal.
SIDE COVER
REMOVAL/INSTALLATION
Right side:Remove the socket bolt [1] and collar [2].
Remove the socket bolt [1].
Release the boss [3] from the frame grommet, then
remove the side cover [4] by pulling it rearward.
Installation is in the reverse order of removal.
 • Align the cover grooves with the tabs of the fuel tank shroud.
DISASSEMBLY/ASSEMBLY (LEFT 
SIDE ONLY)
Remove the screws [1] and separate the side lower
cover [2] from the left side cover [3] by releasing its
slots [4] and holes [5] from the hooks and bosses of the
side cover.
Assembly is in the reverse order of disassembly. TORQUE:
Hook bolt: 21 N·m (2.1 kgf·m, 15 lbf·ft)
[3][1]/[2]
Left side:
[3]
[1]
[4]
Align
[2] (Right side only)
TORQUE:Left side cover assembly screw:0.9 N·m (0.1 kgf·m, 0.7 lbf·ft)
[1]
[3][4]
[5]
[2] 
						

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FRAME/BODY PANELS/EXHAUST SYSTEM
RESERVE TANK COVER
REMOVAL/INSTALLATION
Remove the trim clips [1], socket bolt [2] and reserve
tank cover [3].
Installation is in the reverse order of removal.
 • Align the cover boss [4] with the hole [5] of the stay.
FUEL TANK SHROUD
REMOVAL/INSTALLATION
Right side only:Remove the reserve tank cover (page 2-4).
Remove the side cover (page 2-3).
Remove the socket bolt A [1], socket bolts B [2] and fuel
tank shroud [3].
Installation is in the reverse order of removal.
DISASSEMBLY/ASSEMBLY
Right side:Remove the four screws [1] and separate the grille [2]
and front shroud [3] from the rear shroud [4] by
releasing its tabs [5] and boss [6] from the slots and
hole of the rear shroud.
Remove the two screws [1] and separate the front
shroud [3] from the rear shroud [4] by releasing its tabs
[5] and boss [6] from the slots and hole of the rear
shroud.
Assembly is in the reverse order of disassembly.
[2]
[3]
[1]
[5]
[4]
[2]
[3]
[1]
Left side:
TORQUE:Fuel tank shroud assembly screw:0.9 N·m (0.1 kgf·m, 0.7 lbf·ft)
[3]
[5]
[2] (Right 
side only)
[4]
[1][6]
[1] (Right 
side only) 
						

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FRAME/BODY PANELS/EXHAUST SYSTEM
SKID PLATE
REMOVAL/INSTALLATION
Remove the two bolts [1] and skid plate [2].
Installation is in the reverse order of removal.
 • Align the rear side of the skid plate with the frameslot [3].
HEADLIGHT COWL
REMOVAL/INSTALLATION
Remove the four bolt/was hers [1] and headlight cowl
[2].
Disconnect the headlight 3P (Black) connector [3] and
position light 2P (Black) connector [4].
Installation is in the reverse order of removal.
FRONT FENDER
REMOVAL/INSTALLATION
Remove the four bolt/washers  [1], front fender [2] and
collars [3]
Installation is in the reverse order of removal.
[2][3]
[1]
TORQUE:
Headlight cowl mounting bolt:
8.5 N·m (0.9 kgf·m, 6.3 lbf·ft)
[2][3]
[1]
[4]
[2]
[3]
[1]