Contributed by Ton Hougee
Groningen, Netherlands
Email: ta.hougee@planet.nl
BRAKE SYSTEM
CHARGING SYSTEM / ALTERNATOR
CLUTCH
COOLING SYSTEM
CRANKCASE / PISTON / CRANKSHAFT
CYLINDER HEAD
FINAL DRIVE FRONT WHEEL / SUSPENSION / STEERING
FUEL SYSTEM
GEARSHIFT LINKAGE / TRANSMISSION
IGNITION
LUBRICATION SYSTEM
REAR WHEEL / SUSPENSION
STARTER
ENGINE WILL NOT START / HARD TO START
ENGINE LACKS POWER
POOR IDLE / LOW SPEED PRFORMANCE
POOR HIGH SPEED PERFORMANCE
POOR HANDLING
Brake lever/pedal soft or spongy
---Air bubbles in the hydraulic system
---Leaking hydraulic system
---Contaminated brake pad/disc
---Worn caliper piston seal
---Worn master cylinder piston cups
---Worn brake pad/disc
---Contaminated caliper
---Caliper not sliding properly
---Low brake fluid level
---Clogged fluid passage
---Warped/deformed brake disc
---Sticking/worn caliper piston
---Sticking/worn master cylinder piston
---Contaminated master cylinder
---Bent brake lever/pedal
Brake lever/pedal hard
---Clogged/restricted brake system
---Clogged/restricted fluid passage
Brake drag
---Mis-aligned wheel
---Badly worn brake pad/disc
Return to top of TROUBLESHOOTER
In order to obtain accurate test readings when checking charging system, the battery must be fully charged and in good condition.
Measure the battery current leakage amperes
Check the regulator/rectifier unit inspection
Correct
---Shorted wire harness
---Faulty ignition switch
Incorrect
---Faulty regulator/rectifier
Inspect the regulated voltage
Check the battery using a Honda Battery Tester
---Electric system overloading
---Faulty battery
Not charging
Check the voltages of the regulator/rectifier battery charging line and ground line
Abnormal
---Open circuit in wire harness
----Poorly connected connectors
Normal
Check the alternator(charging and field coils)resistance at the regulator/rectifier connector
Check the charging and field coils at alternator
---Faulty alternator
---Poorly connected alternator connector
Alternator Normal
Clutch lever soft or spongy
---Air bubbles in hydraulic system
---Low fluid level
Clutch slips
---Sticking hydraulic system
---Worn discs
---Weak clutch springs
---Hydraulic system clogged
Clutch lever too hard
---Sticking master piston
---Sticking slave cylinder piston
---Clogged hydraulic system
Clutch operation feels rough
---Rough clutch outer slots
Clutch will not disengage or motorcycle creeps with clutch disengaged
---Warped plate
---Loose clutch lock nut
---Oil level too high, improper oil viscosity or oil additive used
---Leaking or sticking hydraulic system
Engine temperature too high
---Faulty radiator cap
---Insufficient coolant
---Passages blocked in radiator, hoses, oil cooler, or water jacket
---Air in system
---Faulty water pump
---Thermostat stuck closed
---Faulty cooling fan motor
---Faulty fan motor switch
Engine temperature too low
---Faulty temperature gauge sensor
---Thermostat stuck open
---Faulty cooling fan motor switch
Coolant leaks
---Faulty pump mechanical seal
---Deteriorated 0---rings
---Damaged or deteriorated cylinder head gasket
---Loose hose connection or clamp
---Damaged or deteriorated hoses
CRANKCASE/PISTON/CRANKSHAFT
Excessive noise
---Worn connecting rod bearings---Bent connecting rod
---Worn crankshaft main journal bearing
Engine top-end problems usually affect engine performance.
These can be diagnosed by a compression or leak-down test,
or by tracing noises to the top-end with a sounding rod or stethoscope.
If performance is poor at low speeds, check for white smoke in the crankcase breather tube.
If the tube is smoky, check for a seized piston ring.
Compression too low, hard starting or poor performance at low speed
--Valves
---Incorrect valve clearance
---Burned or bent valves
---Incorrect valve timing
---Broken valve spring
---Uneven valve seating
---Sticking valve
--Cylinder head
---Leaking or damaged head gasket
---Warped or cracked cylinder head
---Sticking or broken valve spring
---Damaged or worn camshaft
---Loose or damaged timing belt
---Weak or damaged belt tensionor
---Damaged timing belt pulleys
Rough idle
---Low cylinder compression
Compression too high, overheating or knocking
---Excessive carbon build-up in cylinder head or combustion chamber
Excessive smoke
---Worn valve stem or valve guide
---Damaged stem seal
FINAL DRIVE
Excessive noise in final drive
---Worn or damaged ring gear and driven flange
---Damaged driven flange or wheel hub
---Worn or damaged pinion gear and/or pinion joint splines
---Excessive backlash between pinion and ring gears.
---Low oil level
Excessive rear wheel backlash
---Worn driveshaft splines
---Excessive backlash between ring gear and pinion gear
---Worn driven flange and ring gear splines
---Excessive play in final drive case bearings
---Worn driveshaft and or pinion joint splines
Oil leak at final gear case
---Clogged breather hole
---Oil level too high
---Faulty oil seal(s)
FRONT WHEEL/SUSPENSION/STEERING
Hard steering
---Steering head bearing adjustment nut too tight
---Faulty steering head bearings
---Damaged steering head bearings
---Insufficient tire pressure
---Faulty tire
Steers to one side or does not track straight
---Bent fork
---Bent front axle: wheel installed incorrectly
---Bent frame
---Worn wheel bearings
---Worn swingarm pivot bearings
Soft suspension
---Weak fork springs
---Insufficient fluid in fork
---Low fluid level in fork
---Faulty anti-dive system
Hard suspension
---Incorrect fluid weight
---Bent fork tubes
Front suspension noise
---Loose fork fasteners
---Lack of grease in speedometer gearbox
Front wheel wobbling
---Bent rim
---Worn front wheel bearings
Wheel turns hard
---Brake mis-adjusted
---Faulty wheel bearings
---Faulty speedometer gear
Engine won't start
Too much fuel getting to the engine
---Air cleaner clogged
---Flooded carburetor
---Intake air leak
---Fuel contaminated/deteriorated
---Bystarter circuit clogged
---No fuel to carburetor
---Fuel filter clogged
---Fuel line clogged
---Fuel level mis-adjusted
---Fuel tank breather tube clogged
---Fuel pump malfunction
---Auto fuel valve malfunction
Lean mixture.
---Fuel jet clogged
---Float valve faulty
---Float level too low
---Fuel line restricted
---Carburetor air vent tube clogged
---Vacuum piston faulty
---Throttle valve faulty
Rich mixture
---Bystarter valve open
---Float level too high
---Air jets clogged
---Air cleaner element contaminated
Engine stall, hard to start, rough idling
---Ignition malfunction
---Fuel mixture too lean/rich
---Idle speed mis-adjusted
---Float level mis-adjusted
---Pilot screw mis-adjusted
---Air vent control valve faulty
---Hoses of the emission control system faulty
---Purge control valve faulty
Afterfire when engine braking is used
---Lean mixture in slow circuit
---Air cut-off valve malfunction
---Secondary air supply system faulty
---Hoses of emission control system faulty
Afterfire or misfiring during acceleration
---Ignition system malfunction
---Fuel mixture too lean
Poor performance (driveability) and poor fuel economy
---Fuel system clogged
---Faulty air vent control valve
---Damaged/mis-connected emission control system hoses
GEARSHIFT LINKAGE/TRANSMISSION
Hard to shift
---Improper clutch operation
---Incorrect engine oil weight
---Bent shift forks
---Bent shift fork shaft
---Bent shift fork claw
---Damaged shift drum cam groove
---Bent gearshift spindle
Transmission jumps out of gear
---Worn gear dogs or slots
---Broken shift drum stopper arm
---Worn or bent shift forks
---Broken shift linkage return spring
No spark at all plugs (Faulty input system) If there is no spark at all plugs, the problem could be at the input of the ignition system
Possible system:
---pulse generator
---power input circuit of the spark unit
---neutral switch
---side stand switch---spark unit
---Check for loose or poorly connected spark unit connector.
---Check for loose or poorly connected ignition coil 3P mini connector.
---Check if battery voltage is measured between power input line (Black/White) and ground (Green) at the spark unit connector with the ignition switch ON and the engine stop switch at RUN
---Faulty ignition switch or engine stop switch
---Loose or poor contact of related circuit connectors
---Faulty bank angle sensor relay
---Faulty bank angle sensor
---Measure the pulse generator resistance at the spark unit connector
---Check the neutral switch for continuity at the spark unit connector
Alternator
---Open circuit between the unit and pulse generator
---Loose or poor contact of the pulse generator connector
---Check the neutral switch.
Faulty neutral switch
---Open circuit between the unit and neutral switch
---Loose or poor contact of the neutral switch connectors
---Faulty spark unit
Faulty side stand switch
---Open circuit between the unit and side stand switch
---Loose or poor contact of the side stand switch connector
No spark at either ignition group
---If there is no spark at either group, the problem is suspected in the primary coil side of the ignition system ignition coil, or unit and ignition coil circuit.
Switch the ignition coil primary terminal connection between the faulty pair and the good pair
Try spark test again, if "No Spark" condition: shifts to other pair
Measure resistance of the ignition primary coil at spark unit connector.
---Remove the faulty pair ignition coil and check pair.
---No Spark condition remains with faulty pair
---Faulty ignition coil
---Faulty spark plug wire
---Poor or loose contact of ignition coil SF mini connector
---Open circuit between the unit and ignition coil
---No spark at one plug (Trouble in secondary coil side)
---Faulty spark plug is most likely.
Replace (suspected bad spark plug) with known good spark plug and conduct spark test.
---Original spark plug no good.
---Put the spark plug wire on and measure resistance of ignition secondary coil.
Remove the spark plug wire, and measure the resistance of the ignition secondary coil.---Conduct spark test on good ignition coil.
Faulty ignition coil
---Poor contact of spark plug wire
---Faulty spark plug wire Side stand switch does not function at all.
Side Stand Indicator:
---Check the side stand indicator for function.
Side Stand Switch:
---Check the side stand switch for continuity.
---Faulty side stand switch
---Open circuit in Green/White or Green wire
---Loose or poor contact of related connectors
---Open or short circuit in wire harness
---Burnt indicator bulb
---faulty side stand switch
Oil level low
---Oil consumption
---External oil leak
---Worn piston ring or incorrect piston ring installation
---Worn valve guide or seal
Oil contamination (White appearance?)
From coolant mixing with oil
---Faulty head gasket
---Water leak in crankcase
Low oil pressure
---Pressure relief valve stuck open
---Clogged oil filter screen
---Oil pump worn or damaged
---Internal oil leak
---Incorrect oil being used
No oil pressure
---Oil level too low
---Oil pump drive chain or drive/driven sprocket broken
High oil pressure
---Pressure relief valve stuck closed
---Plugged oil filter, gallery, or metering orifice
REAR WHEEL/SUSPENSION
Rear wheel wobbling
---Worn rear wheel bearing(s)
---Unbalanced tire and wheel
---Low tire promo
---Faulty swingarm pivot bearing(s)
---Damaged shock absorber mount bushing
---Incorrect suspension adjustment
---Bent damper rod
---Damaged swingarm pivot bearing(s)
---Faulty wheel bearing(s)
---Brake drag
---Bent rear axle
---Weak shock absorber spring
---Oil leakage from damper unit
STARTER MOTOR WILL NOT TURN
Check for a blown out main or sub fuses before servicing.
(Make sure the battery is fully charged and in good condition.)
Check for loose or poorly connected battery Abnormal terminals, and open or
shorted battery cable.
---Poorly connected battery terminals
---Open or short circuit in battery cable
Check for loose or poorly connected starter relay switch terminals and 4P connector.
---Poorly connected terminals or 4P connector
Check for loose or poorly connected starter motor cable, and open cable.
---Poorly connected motor cable
---Open circuit in motor cable
With the ignition switch "ON", push the starter switch and check for a "click" sound from the starter relay switch.
Clicks
Connect the starter motor terminal to the battery positive terminal directly. (because a large amount of current flows, do not use thin wires).
Starter motor turns
---Loose or disconnected starter motor cable
---Faulty starter relay switch
Starter motor does not turn
---Faulty starter motor
No click
Disconnect starter relay switch connector, and check the relay coil ground wire
lines as below for continuity:
-Green/Red terminal-clutch switch diode-neutral switch line (with transmission in neutral and clutch lever released.)
-Green/Red terminal-clutch switch-side stand switch line (in any gear except neutral, and with the clutch lever pulled in and the side stand up.)
No continuity
---Faulty neutral switch
---Faulty clutch switch diode
---Faulty clutch switch
---Loose or poor contact of connector
Continuity
Connect the starter relay switch connector. With the ignition switch ON and the
starter switch pushed, measure the starter relay voltage at the
starter switch connector (between Yellow/Red (+) and ground (-)
No voltage
---Faulty starter switch
---Blown out main or sub fuses
Battery Voltage Measured
Check the starter relay switch operation.
---Loose or poor contact of the starter relay switch connector
---The starter motor turns when the transmission is in neutral, but does not turn with the transmission in any position except neutral, with the side stand up and the clutch lever pulled in.
Check the side stand indicator operation with the ignition switch ON
---Burnt bulb
Check the clutch switch operation
Check the side stand switch.
---Lean or poor contact of connector
Starter motor turns slowly
---Low specific gravity in battery (or dead battery
---Poorly connected battery terminal cable
---Poorly connected starter motor cable
---Poorly connected battery ground cable
Starter motor turns, but engine does not turn
---Starter motor is running backwards
---Case assembled improperly
---Terminals connected improperly
---Faulty starter clutch
---Damaged or faulty starter pinion
---Damaged reduction gears
Starter relay switch "clicks", but engine does not turn over
---Crankshaft does not turn due to engine problems
---Excessive reduction gear friction
ENGINE DOES NOT START OR IS HARD TO START
Check fuel flow to carburetor
Not Reaching Carburetor
---Clogged fuel tube or fuel filter
---Sticking float valve
---Faulty fuel pump
---Faulty fuel Pump relay
---Clogged fuel tank breather
---Disconnected or faulty auto fuel vain vacuum tube
Reaching Carburetor
Perform a spark test
Weak or no spark
---Faulty spark plugs
---Fouled spark plugs
---Broken or shorted spark plug wires
---Broken or shorted ignition coil
---Faulty pulse generator
---Faulty engine stop switch
---Loose or disconnected ignition system wires
Good spark
Test cylinder compression
Low compression
---Improper valve clearance (shim too thick)
---Improper valve and seat contact
---Valve stuck open
---Worn cylinder and piston rings
---Damaged cylinder head gasket
---Seized valve
---Improper valve timing
Compression normal
Start by following normal procedure
Engine starts but stops
---Improper choke operation
---Carburetor incorrectly adjusted
---Intake pipe leaking
---Improper ignition timing (Faulty spark unit or pulse generator)
---Fuel contaminated
Engine does not fire
Remove and inspect spark plugs
Wet plug
---Carburetor flooded
---Choke closed
---Throttle valve open
---Air cleaner dirty
Raise wheels off ground and spin by hand
Wheel do not spin freely
---Brake dragging
---Worn or damaged wheel bearings
---Wheel bearings need lubrication
---Final gear bearing damaged
Wheel Spins Freely
Check tire pressure
Pressure Low
---Faulty tire valve
Pressure Normal
Accelerate rapidly from low to second
Engine speed does not increase
---Clutch slipping
---Worn clutch discs/plates
---Warped clutch discs/plates
---Weak clutch spring
---Sticking clutch hydraulic system
Engine speed lowered when clutch is released
Accelerate lightly
Engine Speed Does Not Increase
---Carburetor choke closed
---Clogged air cleaner
---Restricted fuel flow
---Clogged muffler
---Faulty fuel pump relay
Engine Speed Increases
Check ignition timing
Check valve clearance
---Improper valve adjustment
---Worn valve seat
Too Low
---Leaking head gasket
Check carburetor for clogging
Clogged
---Carburetor not serviced frequently enough
Not Clogged
Remove spark plug
Fouled or Discolored
---Plugs not serviced frequently enough
---Spark plugs are incorrect heat range
Not Fouled or Discolored
Check oil level and condition
---Contaminated oil
Remove cylinder head cover and inspect lubrication
Valve train NOT lubricated properly
---Clogged oil passage
---Clogged oil control orifice
---Faulty oil pump
Valve train lubricated properly
Check for engine overheating
Overheating
---Coolant level low
---Fan motor not working (Faulty fan motor switch)
---Excessive carbon build-up in combustion chamber
---Use of poor quality fuel
---Lean fuel mixture
---Wrong type of fuel
Not Overheating
Accelerate or run at high speed
Engine Knocks
---Worn piston and cylinder
---Ignition timing too advanced (Faulty spark unit)
Engine Does Not Knock
POOR PERFORMANCE AT LOW AND IDLE SPEEDS
Check ignition timing and valve
Incorrect clearance
---Improper valve clearance
---Improper ignition timing
--Faulty spark unit
--Faulty pulse generator
Check carburetor pilot screw adjustment
Check for leaking intake pipe
Leaking
---Loose insulator clamps
---Damaged insulator
No Leak
Perform spark test
Weak or intermittent spark
---Faulty, carbon or wet fouled spark plug
---Faulty aide stand switch
Good Spark
POOR PERFORMANCE AT HIGH SPEED
Check ignition timing and valve clearance
Disconnect fuel tube at carburetor
Fuel Flow Restricted
---Clogged fuel line
---Clogged fuel filter
---Faulty fuel pump or relay
---Fuel tank empty
---Faulty auto fuel valve
Fuel Flows Freely
Remove carburetor and check for clogged jets
Clean
Check valve timing
----Camshaft not installed properly
----Cam reduction gear not installed properly----Timing marks on the timing belt pulleys not aligned
Check valve spring
Weak
---Faulty spring
Not Weakened
If steering is heavy
---Steering head bearing adjustment
---nut too tight
---Bent steering stem
If either wheel is wobbling
---Excessive wheel bearing play
---Improperly installed wheel hub swingarm
---Pivot bearing excessively worn
---Swingarm pivot adjusting bolt too tight
If the motorcycle pulls to side
---Front and rear wheels not aligned
---Bent swingarm
---Bent front axle