troubleshooting

inxs

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- trouble shooting

- hope this can grow organically over time … comments and suggestions will hopefully correct, complement, improve and extend this
- an engine is basically an air pump
- add fuel, timing and spark, you get an internal combustion engine
- break this system anywhere and you wont get much action

- so your engine turns over ? wont start
- what have you done ? what have you changed, altered, played with, unfixed ?
- air ? fuel ? spark ? …all in the correct ammount and moment ?
- don’t panic…turn the key and petcock/s off, step back …take breath-deep, go do something you really enjoy for a couple of minutes…
fuses ? kill switch ?
battery ? 12.6 V ? put it on charge, brushes ? check charging system
power to coil/s ? points spark ? plugs ?
filters ?
compression ? leak-down test ?
fuel to carbs ? bowls ? cylinders ? floods ?
adjust your cam chain … can readjust warm once you get her running
set your tappets
set your points if you have them .. plugs​

- once you get this far she should be at least spitting and farting enough to attempt setting your carbs …
if she wont idle, look for air leaks ? atu ? massage her pilot jet circuits
once you can get idle, do the idle speed screw/pilot air screw dance
smooth transition through to full throttle ?
synchronise​


- have a read through here for a bit more detail

- timing light

- battery charger

- battery

- small battery


- of course, the best laid plans of mice and men aside, murphy likes to raise his ugly head
- wider problems ?

"Addition by gggGary" A thread with quick links to many common maintenance procedures fully explained and photographed. Jim's 1980 SG Restoration
 
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inxs

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- electric troubleshooting, battery, charging, ignition, indicators


-battery

- wont charge

battery kaputt​
electrolyte level low​
charging system wires broken or shorting​
battery terminals loose or dirty​
voltage regulator defect​
rectifier defect​
alternator brushes worn​
rotor windings broken​

- xsive charging

battery plates shorting​
regulator not earthed properly​
regulator kaputt​

- unstable charging

intermittent short in wiring​
intermittent coil operation in alternator​
mechanical regulator points dirty​
key switch defective​

- the battery should show
at idle........12.6V​
at 1200rpm 13.5V​
at 3000rpm 14.5V​
... if not, read curlys’ guide for the charging system



- ignition

- no or weak spark

battery kaputt or flat​
coils​
spark plug, plug cap, leads​
kill switch​
main switch​
fuse​
broken or dirty connection​

- points burnt or pitted

condensors​

- plugs - oil fouled

worn - rings, bore, valve guides or seals​
blown head gasket​

- plugs - carbon fouled

too rich​
idle speed too high​
plugs too cold​

- plug - electrodes burnt or overheated

too lean​
ign timing wrong​
plugs too hot​
engine overheating​

- indicators

- wont light

bulb burnt​
no earth​
connection broken​

- wont flash

battery low​

- blink speed varies with rpm

battery low​
flasher unit broken​
 
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inxs

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- start system troubleshooting, kick start, e start

- kick start

- no kick presure

worn or broken kick clip​

- kickstart doesn’t return

broken hook on spiral spring – either end​
broken spiral spring anchor point​

- kickstart wont fold in or out

bearing stuck, spring broken or rusted​


- more info kick start


- electric start

- spins - noisy

worn bendix and or primary gear​

- spins but not the motor

worn bendix spring​

- engine turns slowly

low battery​
bad battery terminals​
oil too heavy​
starter brushes worn​
armature bushes worn​

- starter doesn’t turn

low battery​
starter brushes worn​
armature bushes worn​
starter oil seal leaking​

- starter clicks

flat battery​
loose or dirty battery terminals​
solenid broken​

- nothing happens

broken or loose connections in the starter button​
battery loose or disconected​

- more info E-start
 
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inxs

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- engine troubleshooting

- wont start, no spark

ignition not on​
kill switch off or dirty​
low battery​
fuse​
loose or corroded battery terminals​
old, dirty, worn spark plugs​
plugs wet​
wrong plug gap​
plug caps and resistors​
points pitted, dirty, wrong gap, broken cable​
point earthing to plate, terminal insulators broken​
coils​
condensors​

- wont start, spark

no fuel​
fuel delivery - filters, petcocks​
valve timing​
ignition timing​
compression - top end, rings, head gasket, holed piston​
carburetor settings​
float needle, leaky float, float settings​
pilot circuit blocked​
tank cap vent​

- spark one side only

plugs - worn, fouled, defective, dirty, wrong gap​
plug leads, cap and resistor​
points gap, pitting, dirty, earthing, broken wire​
condensor​
coil​

- hard to start

battery flat​
plugs - worn, dirty, gapping, too cold, kaputt​
points - pitted, dirty​
leads cracked, old, dirty​
coils, condensors​
broken or intermittent earth or connections at points, coil​
cam, valve, points timing out​
valve adjustment​
valve seats​
low compression​

- starts, wont run

fuel delivery​
plugs worn or too cold​
tappet setting​
ignition timing​
yellow to safety relay​

- rough idle

plugs – worn, dirty, gapped too wide, too cold​
spark weak - coils, leads​
points gap wrong, pitted​
ignition timing​
atu​
valves not sealing - worn valves, seats, guides​
tappet adjustment​
leaking manifolds both front and rear, butterfly shaft seals​
float height​
petcocks​
water in bowls​
idle adjustment incorrect​
pilot circuits blocked...take note if running cheap pod filters, they block the pilot air jets​

- top end noise

loose tappets​
cam chain loose or worn​
cam/crank-shaft sprocket worn​
ping-spark knock​
worn gudgeon pin and/or small end​
piston knock - worn cylinder​

- bottom end noise

big end bearing knock - esp noticeable at idle​
main bearings​

- transmission noisy

gears worn, pitted​
main and/or counter -shaft splines worn​
primary gear worn​
noisy clutch​

- runs and misfires on accelaration

battery low​
tank cap vent​
water in bowls​
blocked main jet​
diaphragm​
air leaks​
intermittent or loose connection in ignition wires​
ignition timing​
carb settings incorrect​
coils, condensors​

- surges, runs unevenly

fuel delivery​
too lean​
air leaks - manifolds front and rear, butterfly shaft seals, vacuum barbs, diaphragm, choke seal, bowl connectors​
valve adjustment​

- misfires, breaks up when running

low battery​
loose battery cable​
loose or intermittent contact in ignition circuit​

- popping, misfires on decceleration

too lean​
exhaust leaks​

- backfires or kicksback

too advanced​
atu not working​

- overheats

too lean​
too advanced​
too retarded​
oil low or thin​
oil pump defect, blocked galleries​
carbon choking​
plug too hot​
atu not working properly​

- poor operation - low speed

tank cap vent​
battery weak​
weak spark​
ign timing out​
plugs too cold or gap too big​
bad points contact​
valve adjustment​
valve timing incorrect​
valve seat leak​
worn valve guides​
pilot circuit dirty...take note if running cheap pod filters, they block the pilot air jet​
air mix screw not set right​
float level wrong​
air leak​
carb equaliser tube leaking or loose​
caruretor not level​
petcocks blocked​
dirty gas​

- poor operation - high speed

ign timing retarded​
atu​
plugs too cold, gap too small​
points spring weak​
valve timing​
weak valve springs​
broken rings​
coils, condensors​
torn diaphragm​
butterfly valve not opening, not synchronised​
blocked or wrong main jet​
wrong needle setting​
choke on​
carbs not level​
float level too low​
fuel line, filter, petcock partly blocked​
air filter dirty​
dirty gas​

- power loss

tank cap vent​
exhaust pipe loose or broken​
carbon clogging - engine, mufler​
air filter dirty​
ign timing​
plug gap​
valve adjustment, timing​
valve seating​
weak valve springs​
worn cylinder or rings​
blown head gasket​
float levels too low​

- smoking - blue, oil consumption

too much oil​
rings - bore worn​
marked bore​
valve guides, seals​
crankcase breather blocked​

- smoking - black

too rich​
engine is carbon clogged​

- piston siezed

oil level too low​
oil pump not working​
overheating - too lean, too advanced, stuck valves, tappet clearance too small​

- rings and bore worn

low. thin or contaminated oil​
oil pump defect​
no warm-up​
air filter damaged​

- valves - bent, broken, burnt

weak springs​
overrevving​
hitting piston - wrong valve timing​
tight clearances​
too retarded​

- con-rod bearings

oil low, wrong viscosity​
oil contaminated​
overrevving​
too advanced, misfiring at high speed​

- crankshaft bearings

oil low, wrong viscosity​
oil contaminated​
no warm-up​
overrevving​

- cam - lobes or bearings worn

oil low, too thin or contaminated​
no warm-up​
oil pump not working, oil galleries blocked​
tight tappet clearances​
 
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inxs

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- clutch and gearbox troubleshooting

- clutch - slips

adjustment​
not enough play in the clutch cable​
friction plates worn or oil soaked​
friction plates warped​
weak or damaged pressure plate springs​
springs not evenly tensioned​
pressure plate not aligned​
synthetic oil .. recommended is dino juice​

- clutch - drags

adjustment​
oil too heavy or dirty​
pressure plates warped​
gummed pressure plates​
springs not evenly tensioned​
worm gear cracked​
ball bearing missing​
cable binding​
washers missing from clutch assembly​

- clutch - noisy

worn hub bearing​
basket tongues and/or hub splines worn​
primary gear springs broken​
clutch or main -shaft splines worn​
worn or damaged primary gear​

- clutch reading

- gearbox - grinds when shifting, shifting is difficult

clutch adjustment​
oil too heavy​
bent, damaged or worn shift- forks, pins, drum, lever, arm, spring​
counter or main -shaft bent or bearings are worn​
worn or damaged gear dogs and receivers​
shift drum stopper spring broken​

- gearbox - noisy

oil low, dirty, too thin​
worn gears - backlash​
transmission shaft bearings worn​

- shift lever doesn’t return

shift shaft bent​
return spring broken or weak​

- wont shift

clutch drag​
shift forks bent​
shift return spring broken​
shift shaft bent or circlip lost​

- jumps out of gear

shift drum stopper spring broken​
shift lever adjustment​
gear dogs and receivers worn​
shift forks worn or bent​
shift drum worn​
bent or damaged shift shaft or shift shaft arm​
counter or main -shaft splines worn​
gear teeth worn or broken​
 
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inxs

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- carburetor troubleshooting

- floods

floats set too high​
float sticking, misaligned​
float needle seat worn or damaged​
BS34, float needle body o ring defect​
BS38, float needle body washer defect​
float ruptured​

- lean - idle

pilot jet too small​
air leak​
pilot air screw not adjusted properly​
slide worn​
cheap pod filter blocking air jet​

- lean - acceleration

float level too low​
jets clogged​
worn or damaged slide​

- lean - midrange

air leak​
main or needle jet clogged​

- lean - high speed

float level too low​
main jet too small​
main jet blocked​

- lean - full range

tank cap vent​
filters blocked​
air leaks​
worn slide​

- rich - idle

pilot air screw incorrectly adjusted​
pilot jet too large​
dirty pilot circuits​
cheap pod filter blocking air jet​

- rich - midrange

flooding​
main jet too big​
dirty air filter​

- rich - high speed

flooding​
main jet too big​
dirty air filter​

- rich - full range

flooding​
dirty air filter​

- carb - chirping

inlet manifold cracked, not sealing to carb​
inlet manifold gasket​
vacuum barb bung​
butterfly shaft seals​
diaphragm​
air filter manifold​
air mix screw o-ring​


- more reading here
 
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inxs

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- frame troubleshooting

- chain - noisy

not lubricated​
slaps - xsive play, worn chain and sprockets​
whines - too tight​

- chain - not straight

wheel alignment​
rear wheel not spaced properly​

- xsive vibration

loose mounting bolts​
frame cracked, broken​
loose spokes​
wheels not balanced - particularly the front​
rims not true​
wheel bearings​
tyres worn, damaged, wrong pressure​
axle or swingarm nuts loose​
steering head bearings​
swingarm bushes or bearings​
badly worn chain and sprockets​
crankshaft bearings​
forks bent or not aligned, unequal oil levels​
no fork brace​
rear shocks​
handle bar mounts worn​
foot peg rubbers worn​


- front forks

too much, too little or unequal oil levels​
oil- wrong viscosity, dirty​
seals leaking​
springs - weak, broken, collapsed​
bent tubes​
slider deformed from alu removal or polishing heat​
no fork brace​
fork slider bush is worn - noisy, play​

- steering is stiff

front tyre pressure is low​
steering damper too tight​
steering head bearings too tight​
bearings dry or damaged​
steering stem is bent​
rear shocks uneven​


- uncertain handling

low tyre pressures​
steeringhead bearings worn or loose​
rear shocks defect, unequal, not set for load​
swingarm bushes or bearings are worn​
loose axle​
loose spokes​
rim untrue​

- pulls to one side

bent forks or axle​
unbalanced suspension operation​

- brakes - squeal

linings or pads glazed, hard, worn, damaged​
dirty linings, drum or disc​

- brakes, disc - xsive lever travel, power loss

lines leaking​
air in lines​
master cylinder low​
piston o ring leaking​

- brakes, disc - normal travel, power loss

disc distorted​
pads - worn, damaged or dirty​

- brakes, disc - shudders

disc warped​
loose mounting bolts​
dirty pads​
worn, damaged or distorted pads​

- brakes, disc - scored

dirty pads​

- brakes, drum – don’t hold

adjustment​
linings worn, wet, oily, glazed​
drums worn or damaged​

– brakes, drum – on-off feel

drum not round​
uneven road surface​
 

inxs

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- oil, filter, pump

– sump filter

black plasticy bits – front cam chain guide worn and damaged​
large metal pieces – gear dogs from 5th main and 3rd pinion gear, broken gear teeth, bearing cages​
aluminium – piston holed, piston skirts, clutch basket tongues, kick start spring anchor, casing pieces, worn front cam chain guide​
dirt from clutch friction plates​
copper from crank washers​
petrol from flooding carbs​
filter ruptures from oil return or acceleration while cold oil is too thick​

- side filter

find same things in the filter only smaller size​

- oil pump

- low pressure

filters blocked​
pump rotor worn​
oil passages dirty or blocked​

- no delivery

no oil​
filters blocked​
pump drive gear broken​
shaft broken​
rotor assembly broken or damaged​
oil passage blocked​
restrictor blocked​

- oil filters

- oil leaks

crank seal - behind the alternator​
clutch push rod bush and seal, scroll down - replace short rods with a long one​
drive shaft seal - behind front sprocket, often only needs the nut tightening​
engine base - this may actually be migrating from the front pipe or the cam chain tensioner nut​
head gasket - often resulting from lack of head nut torque control​
crankcase breather - too much oil, worn rings​
cases - unclean or marked surfaces, torn gasket​
fork seals​
 
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corbshere

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my '72 XS650 won't start'seems to be getting gas, no apparent sparks. after cranking a few times plugs are wet with gas, can see no spark at either plug..................Whats next ? how do I check for ciol failure? any other Ideas?
 

corbshere

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I can see the wires coming ito the points on my XS650 1972 yamaha but for the life of me I do NOT see the condensor for each point where is it located .....this is probably silly but I DO NOT SEE THE CONDENSOR on this bike and yet I'm aware they are here some where! help!!!
 

gggGary

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Yeah it's not hard to do, and you should gaze at this thread while you have the engine mount half undone anyways. Remove each nut, lube the threads and retorque. You may never know how much time effort and disgust this can save you.
 

corbshere

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Yeah it's not hard to do, and you should gaze at this thread while you have the engine mount half undone anyways. Remove each nut, lube the threads and retorque. You may never know how much time effort and disgust this can save you.

Is there a recomended torque for the engine mount nuts?

hey man thanks for the help!:thumbsup:

I just found it hard to believe theywould put the condensor assembly in such a spot!
 

gggGary

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The torque was sneekily hidden in this image. Well the enginee mounts would use the same values as the head bolts if you torque those types of bolts..........
XS650torque-vi.jpg
 

mike1968

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Ok.. I have some tough questions. I have a 1982 heritage special that has a crack in the lower front starter gear. It didn't originally leak as much as it is now. Started as a minor leak then after 2 months of driving and fixing other issues: charging system and lighting concerns I am down to oil leak. I have put JB weld on the inside hoping it would stop the leak. I also was able to get ahold of new starter cover, old one is missing a small peice around the crack. I'm assuming after time the vibration caused the front pin, for placement, to break off. I'm not a mechanic so unsure of what to do looking for some experienced answers. I have thought about taking it to a welder in town that has experience in welding aluminum or I also have seen someone take the gears our and plugged up housing. Just uses electric start. I am assuming that the starter gear housing just is for the kick start operation. I wanted to keep everything original. But I have put more money than I was expecting into the motorcycle. I love to ride but also have other expenses. Any ideas on what to try next. I had a beginner mechanic work on it and he feels that the rest of the cycle is good. He has it sounding great. Synced the carbs, I put a new rotor and more into the charging system. Looking at the best route to go. I don't want to sell, but also don't want to keep putting money in and not riding it. I have some pictures if it would help determine.
 

streetillegal

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after a near disastorous loss of power going home last week i got my 77 yam 650xsd running great after a thurough gearbox oil filter yadda yadda inspection and oil change . have been having problems with keeping a charge only cuz i lost my key n had to file a new one but i forget to turn it off alot anyway i had charger on and started my bike perfect turned it off went inside to get ready for my 45 min ride home (at girlies) started bike took off charger and it died , my alternator ,last i checked put out 14.3 v, i donot have a multimeter wit me now it will not start it has spark fuel air filters are clean so WTF is up i got to get outta here shes drivin me nuts Help
 
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