Handy Troubleshooting Guide ( ST1100 ) *

[KoTAOW]

Original web page can be viewed here:  http://www.johnandbecci.info/Hints/ts.htm

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Troubleshooting Guide

Part #1


BRAKE SYSTEM

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

---Sticking/worn caliper piston

---Caliper not sliding properly

---Clogged/restricted fluid passage

---Worn caliper piston seal

---Sticking/worn master cylinder piston

---Bent brake lever/pedal

Brake drag

---Contaminated brake pad/disc

---Mis-aligned wheel

---Badly worn brake pad/disc

---Warped/deformed brake disc

---Caliper not sliding properly

---Clogged/restricted fluid passage

---Sticking/worn caliper piston


CHARGING SYSTEM / ALTERNATOR

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

Correct

Check the battery using a Honda Battery Tester

Incorrect

---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

Abnormal

Check the charging and field coils at alternator

Abnormal

---Faulty alternator

Normal

---Poorly connected alternator connector


Alternator Normal

Check the regulator/rectifier unit inspection

Abnormal

---Faulty regulator/rectifier


CLUTCH

Clutch lever soft or spongy

---Air bubbles in hydraulic system

---Low fluid level

---Leaking hydraulic system

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

---Sticking master piston

---Sticking slave cylinder piston

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

---Air bubbles in hydraulic system

---Low fluid level

---Leaking or sticking hydraulic system


COOLING 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

---Faulty radiator cap

---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


CYLINDER HEAD

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

Excessive noise

---Incorrect valve clearance

---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

---Faulty steering head bearings

---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

---Clogged fluid passage

Front suspension noise

---Insufficient fluid in fork

---Loose fork fasteners

---Lack of grease in speedometer gearbox

Front wheel wobbling

---Bent rim

---Worn front wheel bearings

---Faulty tire

Wheel turns hard

---Brake mis-adjusted

---Faulty wheel bearings

---Faulty speedometer gear


FUEL SYSTEM

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

---Intake air leak

---Fuel pump malfunction

---Auto fuel valve malfunction

---Vacuum piston faulty

---Throttle valve faulty

Rich mixture

---Bystarter valve open

---Float valve faulty

---Float level too high

---Air jets clogged

---Air cleaner element contaminated

---Flooded carburetor

---Vacuum piston faulty


Engine stall, hard to start, rough idling

---Fuel line restricted

---Ignition malfunction

---Fuel mixture too lean/rich

---Fuel contaminated/deteriorated

---Intake air leak

---Idle speed mis-adjusted

---Float level mis-adjusted

---Fuel tank breather tube clogged

---Fuel pump malfunction

---Pilot screw mis-adjusted

---Bystarter circuit clogged

---Auto fuel valve malfunction

---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

---Ignition system malfunction

---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


IGNITION


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

---Open circuit in wire harness

---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

---Faulty spark unit

---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


LUBRICATION SYSTEM

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

---Low oil level

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

---Incorrect oil being used


REAR WHEEL/SUSPENSION

Rear wheel wobbling

---Bent rim

---Worn rear wheel bearing(s)

---Faulty tire

---Unbalanced tire and wheel

---Low tire promo

---Faulty swingarm pivot bearing(s)

Hard suspension

---Damaged shock absorber mount bushing

---Incorrect suspension adjustment

---Bent damper rod

---Damaged swingarm pivot bearing(s)

Wheel turns hard

---Faulty wheel bearing(s)

---Brake drag

---Bent rear axle

Soft suspension

---Weak shock absorber spring

---Oil leakage from damper unit

---Incorrect suspension adjustment


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.

Abnormal

---Poorly connected battery terminals

---Open or short circuit in battery cable

Normal

Check for loose or poorly connected starter relay switch terminals and 4P connector.

Abnormal

---Poorly connected terminals or 4P connector

Normal

Check for loose or poorly connected starter motor cable, and open cable.

Abnormal

---Poorly connected motor cable

---Open circuit in motor cable

Normal

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

---Faulty side stand switch

---Loose or poor contact of connector

---Open circuit in wire harness

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 ignition switch

---Faulty starter switch

---Blown out main or sub fuses

---Loose or poor contact of connector

---Open circuit in wire harness

Battery Voltage Measured

Check the starter relay switch operation.

Normal

---Loose or poor contact of the starter relay switch connector

Abnormal

---Faulty starter relay switch

---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

Abnormal

---Faulty side stand switch

---Burnt bulb

---Open circuit in wire harness

Normal

Check the clutch switch operation

Abnormal

---Faulty clutch switch

Normal

Check the side stand switch.

Abnormal

---Faulty side stand switch


Normal

---Open circuit in wire harness

---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

---Faulty starter motor

---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


Contributed by Ton Hougee
Groningen, Netherlands

[KoTAOW]

Troubleshooting Guide

Part #2


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

---Faulty spark unit

---Broken or shorted spark plug wires

---Broken or shorted ignition coil

---Faulty ignition switch

---Faulty pulse generator

---Faulty engine stop switch

---Faulty bank angle sensor

---Faulty bank angle sensor relay

---Faulty side stand 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


ENGINE LACKS POWER

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

---Clogged fuel tank breather

---Faulty fuel pump

---Faulty fuel pump relay

Engine Speed Increases

Check ignition timing

Incorrect

---Faulty spark unit

---Faulty pulse generator

Correct

Check valve clearance

Incorrect

---Improper valve adjustment

---Worn valve seat

Correct

Test cylinder compression

Too Low

---Valve stuck open

---Worn cylinder and piston rings

---Leaking head gasket

---Improper valve timing

---Seized valve

---Improper valve and seat contact

Normal

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

Incorrect

---Oil level too high

---Oil level too low

---Contaminated oil

Correct

Remove cylinder head cover and inspect lubrication

Valve train NOT lubricated properly

---Clogged oil passage

---Clogged oil control orifice

---Contaminated oil

---Faulty oil pump

Valve train lubricated properly

Check for engine overheating

Overheating

---Coolant level low

---Fan motor not working (Faulty fan motor switch)

---Thermostat stuck closed

---Excessive carbon build-up in combustion chamber

---Use of poor quality fuel

---Clutch slipping

---Lean fuel mixture

---Wrong type of fuel

Not Overheating

Accelerate or run at high speed

Engine Knocks

---Worn piston and cylinder

---Wrong type of fuel

---Excessive carbon build-up in combustion chamber

---Ignition timing too advanced (Faulty spark unit)

---Lean fuel mixture


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


Correct

Check carburetor pilot screw adjustment

Correct

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 spark unit

---Faulty ignition coil

---Broken or shorted spark plug wires

---Faulty engine stop switch

---Faulty pulse generator

---Faulty ignition switch

---Faulty bank angle sensor

---Faulty bank angle sensor relay

---Faulty aide stand switch

---Loose or disconnected ignition system wires

Good Spark


POOR PERFORMANCE AT HIGH SPEED

Check ignition timing and valve clearance

Incorrect

---Improper valve clearance

---Improper ignition timing

---Faulty spark unit

---Faulty pulse generator

Correct

Disconnect fuel tube at carburetor

Fuel Flow Restricted

---Clogged fuel line

---Clogged fuel tank breather

---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

Clogged

Clean


Not Clogged

Check valve timing

Incorrect

----Camshaft not installed properly

----Cam reduction gear not installed properly----Timing marks on the timing belt pulleys not aligned

Correct

Check valve spring

Weak

---Faulty spring

Not Weakened


POOR HANDLING

Check tire pressure

If steering is heavy

---Steering head bearing adjustment

---nut too tight

---Damaged steering head bearings

---Bent steering stem

If either wheel is wobbling

---Excessive wheel bearing play

---Bent rim

---Improperly installed wheel hub swingarm

---Pivot bearing excessively worn

---Bent frame

---Swingarm pivot adjusting bolt too tight

If the motorcycle pulls to side

---Front and rear wheels not aligned

---Bent fork

---Bent swingarm

---Bent front axle

---Bent frame

Contributed by Ton Hougee
Groningen, Netherlands