Erratic ignition now no power, no start

[BigTon]

My 2000 SV650S died last week. I cant work out what caused it! Any help would be much appreciated.
Battery has past its best but was fully charged and ok. Rode about 8 miles to meet everyone then went about 20 miles and stopped to regroup, all seemed fine.
When I fired the bike back up (10 minutes later) everything still seemed fine but when I pulled off I my indicator light was flashing, fuel light flashing and I think oil light on. Also rev and speedo needles were bouncing back on forth randomly.
I pulled over and stopped but it wouldn't start again! No ignition lights at all! It seemed like there was no power anywhere? No lights, horn or anything
A few roadside checks showed...
No power with different battery or jump leads
Ignition fuse ok (swapped with spare just incase)
starter fuse (30a) ok (swapped with spare)
Sparking from starter terminals, engine turned over and started twice but cut out shortly after. Engine turning but no start since.

After getting the bike home i found that there is power to the fuse box above the battery but I've not checked any other components as i'm not sure where to start. I did notice when stripping the bike though that the clutch switch has been bypassed. Maybe this has caused something?

Also, the only thing that I did different to normal is when I stopped I just cut the engine cut off switch and left it in gear. And when I started it left it in gear, clutch in and pressed the button. I'm not sure if the would have caused something to go wrong?

[Bibio]

my first check would be the ignition connector.

[R1ffR4ff]

Also check for corrosion in the Big Block connector under the tank at the front near the headstock.

Also pull and check all fuses and their slots for corrosion.

[BigTon]

I'll have a look this week, thanks :)

[BigTon]

OK, so ive done a bit of probing with my multi-meter. As far as I can tell (and i'm no expert) there is power going to the fuse box, r+r and ignition switch but nothing going to the instrument cluster. No parking lights or horn, nothing. I tried this with a spare instrument cluster too and same result and so i'm pointing the blame at the ignition switch and on the look out for a new one.
Fingers crossed this gets me back on the road, ive just paid for new chain and sprockets last month!

[Bibio]

you need to physically check the terminals inside the connector for the ignition switch for corrosion.

after that its the kill switch.

[BigTon]

UPDATE!
OK, ive changed the ignition switch and still have the same problem.
How can I have zero power? No mileage, horn, nothing!
There does not appear to be any power at the ignition fuse.
Red wire on ignition switch connector shows either 6v or 1v
If the kill switch was faulty surely there would still be ignition lights at least?
I really don't know what to test first now or in what order

[BigTon]

Ok thank you I’ll check that tomorrow [emoji1303]


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[andy650]

The wiring loom can chaff and fail, where it passes next to the tank hinge, worth a quick look.

[BigTon]

The wiring loom can chaff and fail, where it passes next to the tank hinge, worth a quick look.



Thanks, I’ll check that too.
I don’t think there is any power going to the fuse box at all? The starter terminals spark so I have power there.

The original symptoms ie. erratic ignition were what happened just before having zero power.


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[embee]

3 other places where curvy wiring harnesses chafe. Probably not your issue from the description, but worth knowing and checking.
The wiring loops round a frame bracket inside the pillion seat cubby area, left side of the bike towards the rear. Check for chafing.
Both rider's seat bolts can be too long and hit the harness conveniently running just behind them. Check both sides. These are the ones holding the seat on, remove the triangle black panels to reveal them.

I suspect more likely Bibs is on track.

[Bibio]

have you checked the battery voltage when off then on? you need a "perfect" battery to test the electrical system, if your battery is dodgy then you will get dodgy reading. if you know the battery is old then best get a new one.

one of the problems with the curvy clocks is that they draw power directly from the battery/charging system. if someone has replaced the fuse for a higher rated then if jump starting the bike can cause a surge to the clocks, its rare though.

i suspect that you never checked the ignition switch to see if it was the problem first so you might have just wasted money there.

to test the electrical system you need a DMM with thin "needle" probes. using the wiring diagram you start with the main power from battery to the next component to check for power (12-13v) then from that component to the next so on and so on. next up you then systematically check each end of each connector for wire continuity. there is no quick fix.

you can ignore things like indicator and lighting circuits for the time being and concentrate on the power/starting circuits.

the symptoms your describing sound very like what happens when the RR goes open circuit. when this happens you get AC through the electrical system due to the rectifier diodes breaking down. your generator/stator generate AC voltage and your rectifier/regulator turns the AC voltage to DC voltage and then regulates the voltage to a more suitable DC voltage (around 15v).

wires and fuses dont care if the voltage is AC or DC but the electrical components do as they were designed for DC usage. supplying DC components with AC will fry internal circuity.

hope this helps.

[BigTon]

Thanks for all your advice

I have checked all the connectors on the loom that I can see and they’re all spotless. I’ve also checked and can’t see any breaks in the harness either.

Battery is reading 13v

I tried a new ignition switch which made no difference at all.

I’ve tested the turn signal relay and diodes which appear to be working correctly.
I’ve been following your advice working my way along the harness and checking connectors but getting a little confused along the way.
But I noticed that there is 13v going to the meter fuse (3?) but only when the ignition is off. Once the ignition switch is ON I can’t find any power at the fuses. That can’t be right?

Also, how the hell do I get the ground that’s in behind the swing arm? That’s the only one I haven’t checked due to firstly not being able to find it and secondly not being able to access it!

A local garage told me the dancing needles and flashing lights sounds like an ICU fault. There’s no way of testing that unit but should I still have ignition lights if it were faulty? Same with R/R?


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[R1ffR4ff]

What's the voltage across the battery @ idle?

[BigTon]

13v across the battery terminals, what do you mean by idle?


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[R1ffR4ff]

13v across the battery terminals, what do you mean by idle?


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I mean with the engine running at idle speed.

[BigTon]

I mean with the engine running at idle speed.


Ah ok, the engine won’t turn over, it’s completely dead.
When it was running it was idling at 13.8v or something.


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[R1ffR4ff]

Ah ok, the engine won’t turn over, it’s completely dead.
When it was running it was idling at 13.8v or something.


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Ok.I should have read back.It's the ,"No Power" issue.All you can do is keep looking for continuity breaks like you have said things like that ground wire and main power wires.

Also if not already covered look for engine stop points like the side-stand switch/Engine cut-off switch.I had an engine cut-off switch short and cause intermittent none starting on one of my old Hondas.

[BigTon]

Ok.I should have read back.It's the ,"No Power" issue.All you can do is keep looking for continuity breaks like you have said things like that ground wire and main power wires.

Also if not already covered look for engine stop points like the side-stand switch/Engine cut-off switch.I had an engine cut-off switch short and cause intermittent none starting on one of my old Hondas.



Checked side-stand switch and neutral indicator switch also. Both appear to be working correctly according to the manual. I did check the cut off switch but maybe worth double checking. I thought it would still have power though if it were that switch?


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[R1ffR4ff]

Checked side-stand switch and neutral indicator switch also. Both appear to be working correctly according to the manual. I did check the cut off switch but maybe worth double checking. I thought it would still have power though if it were that switch?


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Yeh it should.It's more likely a main power wire/ground.

What state are the actual fuse holder sockets in?

I had a none-starter where the fuse holder looked ok but was open-circuit.

[BigTon]

Yeh it should.It's more likely a main power wire/ground.

What state are the actual fuse holder sockets in?

I had a none-starter where the fuse holder looked ok but was open-circuit.



Fuse holder is clean. Bike is always stored in my garage.


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[BigTon]

I'll say one thing BT, you keep finding things that aren't right!



As a general rule with Suzukis, if it's an Orange wire or an Orange wire with a stripe - that is switched power.



Looking at the colour schematic, there's a red wire going to fuse 5, so that should have 12V power all the time.



There shouldn't be 12V on the other fuses until the ignition is on (ie opposite to what you have).



1) with the ignition off, do you have 12V on the red wire at the ignition switch?

2) with the ignition off, do you have 0V on the orange wire at the ignition switch?

3) with the ignition on, do you have 12V on the orange wire at the ignition switch?



When you measure your voltages are you putting the negative probe on the battery negative terminal or on the bike chassis? (they should read the same voltage).



If you have a short it will direct battery current to ground which would drop your 12V meter reading to 0V but the battery can produce over 100 Amps when shorted so it would melt any wire that wasn't fuse protected - you would smell it and see smoke until burnt through.



I do seem to find thing not right [emoji23]

Ignition off - no power to red wire
Ignition off - 13v at orange wire
Ignition on - power drops to 1v at orange wire
Tested with black probe on batt - and red at the fuse box or connector? Should I try black probe elsewhere?

No smoke or smell when I’ve been testing


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[Bibio]

not trying to be rude but do you understand wiring schematics?

[BigTon]

not trying to be rude but do you understand wiring schematics?



To an extent yes but knowledge is very basic to honest.


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[BoltonSte]

iirc (it's been a while since I had a curvy). We had similar issues with the green connector/starter relay I think on the RHS under the black infill.

[Bibio]

then i would suggest that you take some time to understand the schematic a bit more.

it looks complicated but in reality its very easy. follow the coloured lines till you come to a connector/component then look at the connector/component for the route it takes through and out the other side. sometimes the colour of the wire changes so you need to follow that.

if you have a coloured printer then print the diagram out. get a highlight pen and highlight the wiring you have done, also mark down voltages as you go with power on/off. start from the battery and work your way out.

with fuses the power goes in one end (usually marked with the long line or no fuse at the junction)

with things like switches there are dots/circles with a "bar" connecting them. this is to tell you when things are on/off and what way the voltage flows.

as an example lets look at the ignition switch red wire. when the ignition switch is in the on position the red wire connects to the orange wire. when the ignition is off/lock then there is no power to anything, when the ignition is at park then the red connects to the brown.

so if you put the red probe of your DMM in the orange wire exiting the ignition switch and the black probe on the battery negative terminal there should be no power on the orange wire when the switch is off, when you turn the switch to on then you should get 12-13vdc on the orange wire.

if you get power where there should not be then disconnect the connector and probe the main loom (not the switch) orange wire with the red probe of your DMM. if you still get power then you have to probe deeper into the loom to find out exactly where you are getting the power from. its very very rare that you get reverse voltage and the most common is the battery being connected the wrong way round.. trust me i have seen people do it. or the negative system is shorting to a live.

[Bibio]

iirc (it's been a while since I had a curvy). We had similar issues with the green connector/starter relay I think on the RHS under the black infill.

yup if the positive terminal is touching the frame then it will send the whole system live.

[Bibio]

ooohhh and remember that everything is "live" yes even negative (ground) will show voltage when a switch is switched on.

[BigTon]

Thank you all so much for you time and patience. I finally found the problem!!!
Something I should have checked ages ago going by the symptoms of no power to the fuse box.
Anyone like to guess before I tell?


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[garynortheast]

Battery connection?

[BigTon]

Battery connection?



Nope. That was the first thing I checked


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[Bibio]

blown main fuse or disconnected main battery cable at starter relay.

[garynortheast]

Gwan and tell us then, gwan, gwan, gwan......

[BigTon]

blown main fuse or disconnected main battery cable at starter relay.







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[BigTon]

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Close!


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[BigTon]

After taking advice and looking at the wiring diagram I went back to basics.
Power going to the starter but then it always will have power as it’s connected direct to the battery
However, the wire going from there to the fuse box was burnt out and the plug melted.
So I need to source a new plug from somewhere [emoji57]


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[BigTon]

https://uploads.tapatalk-cdn.com/20180710/25c2d9d7f187d17e1de4ba14379e1c60.jpg


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[garynortheast]

Ouch! That's a bit of a mess. Could easily have been caused by high resistance due to dirty contacts.

[BigTon]

Ouch! That's a bit of a mess. Could easily have been caused by high resistance due to dirty contacts.



Or from it being jumped several times from an Audi with engine running [emoji51]


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[garynortheast]

Or from it being jumped several times from an Audi with engine running [emoji51]


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Ahh! :smt104

[Bibio]

to melt that connector there must have been some serious voltage going through it. so you have a fault elsewhere. or the connecting terminal is furred up causing arcing.

[Bibio]

pretty sure that its these https://www.easternbeaver.com/Main/Elec__Products/Connectors/Sealed/RFW/rfw.html

[BigTon]

to melt that connector there must have been some serious voltage going through it. so you have a fault elsewhere. or the connecting terminal is furred up causing arcing.



After braking down roadside we tried a lot of times jumping the terminals at the starter. Sure that would be enough to melt it?


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[Bibio]

doubt it. unless you had the car running.

i personally think its been fried before jumping the bike from the car and thats why it broke down.

[BigTon]

doubt it. unless you had the car running.

i personally think its been fried before jumping the bike from the car and thats why it broke down.



Yes car was always running [emoji51]


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[R1ffR4ff]

There's never a need to have a car running if jumping a Motorcycle and as you've found out it can ruin components on the Motorcycle.If the extra passive power from the larger Car battery won't start the machine then starting the Donor car won't help.The fault on the Motorcycle needs to be fixed.

Because the internal resistance of the Motorcycle battery will be lower than the Donor battery as it has been depleted the extra current from the Alternator on the car will bypass it's own battery and shunt the current to the smaller and much less robust Motorcycle battery.The danger to the Motorcycle electrics will increase further if the Donor car is revved up :(

[Bibio]

i'll stick my neck out here and say what i think has happened. i'll take a wild guess and say that the burnt out terminal is the red wire. now since the bike had a fault and broke down i'll say that the terminal was already on its way out. the reason for this is that the regulator in the RR is passing too much voltage or the rectification is collapsing and letting AC through, this is really bad news as the AC is at much higher amps. wiring, connectors and fuses dont care if its AC or DC but the terminals in connectors are specified to certain amperage be it AC or DC when the terminals go over their specified amps then they either melt, explode or in this case heat up causing the plastic around it to melt.

[R1ffR4ff]

Absolutely right.As connectors corrode over time and if not halted the surface area of the contacts reduces.The effect is exactly the same as if you say have 1.5mm 20 amp multi wire cable and each year it lost a strand.Eventually it cannot handle the current it was designed for and will start to heat up as it's resistance increases due it it's reduced diameter/surface area.

I've just been fitting a MOSFET R/R and found out something I've not seen noticed on any forum when I've been researching and that is that on my 1999 Curvy Suzuki fitted not just one HT Stator Connector but TWO!.

I've removed both from the Stator lines and the one on the Regulator wires so they are hard wired in now.

I've been making some web pages for it and also have now fitted a small PC cooling fan to the R/R just for good measure.

http://puttingoutfires.x10host.com/MosfetFH020AA/MosfetUniRR.html

Unfortunately it looks like the over-voltage has ruined the Circuit board in the Tacho as it's become unreliable and the 4 year old battery is suspect so it's gone.

Mosfet R/R is working as expected and running between 10-15 Deg C cooler with the the small fan.

[Bibio]

nice write up :-)

notice that you use a clothes peg. might i suggests that you get some blu-tak and use that. its what i use for all my wire soldering and sometimes on circuit boards as well. press blu-tak on a surface then press the wire into the blu-tak with the end you want to work sticking out. if you use two blobs of blu-tak its easier to solder two ends together, keeps your hand free for the iron and solder :-)

[R1ffR4ff]

nice write up :-)

notice that you use a clothes peg. might i suggests that you get some blu-tak and use that. its what i use for all my wire soldering and sometimes on circuit boards as well. press blu-tak on a surface then press the wire into the blu-tak with the end you want to work sticking out. if you use two blobs of blu-tak its easier to solder two ends together, keeps your hand free for the iron and solder :-)

I've used Blu-tac and similar Biblio but I can never find it when I need it.Nice thing about a clothes peg is I can leave it clipped to my Soldering iron so it's always around.

Also I always break the hook things on my soldering irons so I make my own out of some welding wire so I can hook the iron where I need to on-bike :)

[BigTon]

There's never a need to have a car running if jumping a Motorcycle and as you've found out it can ruin components on the Motorcycle.If the extra passive power from the larger Car battery won't start the machine then starting the Donor car won't help.The fault on the Motorcycle needs to be fixed.

Because the internal resistance of the Motorcycle battery will be lower than the Donor battery as it has been depleted the extra current from the Alternator on the car will bypass it's own battery and shunt the current to the smaller and much less robust Motorcycle battery.The danger to the Motorcycle electrics will increase further if the Donor car is revved up :(

Lesson learnt :oops:

i'll stick my neck out here and say what i think has happened. i'll take a wild guess and say that the burnt out terminal is the red wire. now since the bike had a fault and broke down i'll say that the terminal was already on its way out. the reason for this is that the regulator in the RR is passing too much voltage or the rectification is collapsing and letting AC through, this is really bad news as the AC is at much higher amps. wiring, connectors and fuses dont care if its AC or DC but the terminals in connectors are specified to certain amperage be it AC or DC when the terminals go over their specified amps then they either melt, explode or in this case heat up causing the plastic around it to melt.

Your right! 2 years ago I thought I noticed the battery charging at 18v. But every time time I checked it after that it was at 14v so doubted my meter.
Then after a 150m ride, got home for 10 mins then headed to the shop. When I came out the shop the bike didn't have enough power to start (another occasion when jump leads came out). When I got home checked over again and this time it WAS charging at 18v! I have no idea how long this had been happening for so maybe that has caused the block to burn initially. I replaced the RR after that and all seemed fine... until this happened.
When the bike broke down I had rode maybe 30 miles. It must have been just deteriorating over time. Unless the new RR is also faulty?

Absolutely right.As connectors corrode over time and if not halted the surface area of the contacts reduces.The effect is exactly the same as if you say have 1.5mm 20 amp multi wire cable and each year it lost a strand.Eventually it cannot handle the current it was designed for and will start to heat up as it's resistance increases due it it's reduced diameter/surface area.

I've just been fitting a MOSFET R/R and found out something I've not seen noticed on any forum when I've been researching and that is that on my 1999 Curvy Suzuki fitted not just one HT Stator Connector but TWO!.

I've removed both from the Stator lines and the one on the Regulator wires so they are hard wired in now.

I've been making some web pages for it and also have now fitted a small PC cooling fan to the R/R just for good measure.

http://puttingoutfires.x10host.com/MosfetFH020AA/MosfetUniRR.html

Unfortunately it looks like the over-voltage has ruined the Circuit board in the Tacho as it's become unreliable and the 4 year old battery is suspect so it's gone.I found an S set of clocks and bought them off eBay.I checked the part numbers and the clocks are the same so with luck I should be able to get it all sorted by next week.

Mosfet R/R is working as expected and running between 10-15 Deg C cooler with the the small fan.

I have a spare rolling frame with clocks, front fairing and headlights etc. I could have sorted clocks for you if i'd known.

Thanks for the info. Everyday is a school day :D

[R1ffR4ff]

Lesson learnt :oops:



Your right! 2 years ago I thought I noticed the battery charging at 18v. But every time time I checked it after that it was at 14v so doubted my meter.
Then after a 150m ride, got home for 10 mins then headed to the shop. When I came out the shop the bike didn't have enough power to start (another occasion when jump leads came out). When I got home checked over again and this time it WAS charging at 18v! I have no idea how long this had been happening for so maybe that has caused the block to burn initially. I replaced the RR after that and all seemed fine... until this happened.
When the bike broke down I had rode maybe 30 miles. It must have been just deteriorating over time. Unless the new RR is also faulty?



I have a spare rolling frame with clocks, front fairing and headlights etc. I could have sorted clocks for you if i'd known.

Thanks for the info. Everyday is a school day :D

Damn.Ok that's good to know for the future.I've chatted with the ebay guy I'm getting the clocks off and he seems decent :)

As the R/R I've bought is a cheap knock-off I'm wary now so I'm almost certainly going to fit a Voltage meter.Thing with the naked Curvy I'm trying to think which type and where to fit.

There's the single LED type like this,

https://tinyurl.com/yasvo47b

Which some of my old CX500 guys used but I fancy one with a proper read-out like this,

https://www.ebay.co.uk/itm/DC12V-LED-Panel-Car-Motorcycle-Digital-Battery-Monitor-Voltage-Meter-Voltmeter/253601752231?epid=2289998382&hash=item3b0bd7a4a7:g:OGEAAOSwQO9a61TY

And or might be able to strip one of these down for cheaper and better,

https://tinyurl.com/ya7sjpwq

[Bibio]

if its a mosfet then should be good to go unless its a really cheep POS.

voltage dials only tell you when there is over/under voltage and by the time they tell you something is wrong its already caused damage.

[R1ffR4ff]

if its a mosfet then should be good to go unless its a really cheep POS.

voltage dials only tell you when there is over/under voltage and by the time they tell you something is wrong its already caused damage.

I disagree Bib.Voltage increases can be incremental and over time.Some components can handle the increased voltage before failing,some can't.It's a good indication if there's fault if caught in time and some things can be saved.

[BigTon]

if its a mosfet then should be good to go unless its a really cheep POS.

voltage dials only tell you when there is over/under voltage and by the time they tell you something is wrong its already caused damage.



It wasn’t cheap, about £90 from weemoto


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[R1ffR4ff]

It wasn’t cheap, about £90 from weemoto


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It may well have been corroded connectors that may have brought it down if it has failed :(

[BigTon]

It may well have been corroded connectors that may have brought it down if it has failed :(



Looks like the r/r has a burnt out diode.
Testing showed one of the 3 stator connectors on the + side reading 0 while other 2 reading 5.2

I’m not sure exactly what this means but I’ve a new one here and all 3 connectors read the same.


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[R1ffR4ff]

Glad you found the fault.Don't forget to go down the Stator wires and check all the connectors for corrosion.

[Bibio]

if you fitted a decent mosfet RR and it went pop then i would seriously be looking at the stator AC output.

[R1ffR4ff]

if you fitted a decent mosfet RR and it went pop then i would seriously be looking at the stator AC output.

Good call :)

[BigTon]

if you fitted a decent mosfet RR and it went pop then i would seriously be looking at the stator AC output.



That’s what I was thinking [emoji1303]
What should it be?


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[R1ffR4ff]

That’s what I was thinking [emoji1303]
What should it be?


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70v AC @ 5,000 rpm :)

[BigTon]

...between yellow wires 1-2, 2-3, 3-1



I’m getting 80v @5000 rpm




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[Biker Biggles]

All three the same or very similar?If so I think that is OK.

[BigTon]

All three the same or very similar?If so I think that is OK.



They’re all the same. Manual says 60 so not sure if 80 is too high?


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[R1ffR4ff]

I was mistaken when I posted my 70 VAC as mine is the 300w Stator on the Curvy.The,"S" versions I believe use a 275w Stator.

Is it possible some one has upgraded the Stator to a higher powered one?

[Bibio]

as long as all three outputs are the same and MORE than 70VAC and less than 90VAC you have a healthy stator.

the more voltage the stator kicks out the more the regulator has to work so produces a little more heat.

contrary to popular belief its actually bad to run the bike without your lights on. you want to use as much power as you can without sacrificing charging/ignition system. once a battery is fully charged it should only need a trickle from the RR to keep it healthy.

[BigTon]

as long as all three outputs are the same and MORE than 70VAC and less than 90VAC you have a healthy stator.

the more voltage the stator kicks out the more the regulator has to work so produces a little more heat.

contrary to popular belief its actually bad to run the bike without your lights on. you want to use as much power as you can without sacrificing charging/ignition system. once a battery is fully charged it should only need a trickle from the RR to keep it healthy.



Good to know thanks. Maybe I’ll fit some heated grips to use up some power [emoji16]


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[Yellow650Loz]

I think there's a few here mistaking voltage for current.
If the voltage drops then the current draw will be higher.

I.e.

55w @ 12V DC = 4.583 Amps
That's basically one headlamp bulb on a battery and engine off

55w @ 14.9V DC = 3.691 Amps
That's the same bulb but this time the battery is charging....the engine is running.

It's the current that overheats wiring and connectors, not voltage.
Now it could have been a corroded connector that's caused voltage drop and so the current draw has increased. However, I would be cautious as to why it melted in the first place, jump starting a motorcycle from a car is fine. Running or otherwise.

Please don't ever try jump starting a car from a motorcycle though!!!!!

[BigTon]

I think there's a few here mistaking voltage for current.

If the voltage drops then the current draw will be higher.



I.e.



55w @ 12V DC = 4.583 Amps

That's basically one headlamp bulb on a battery and engine off



55w @ 14.9V DC = 3.691 Amps

That's the same bulb but this time the battery is charging....the engine is running.



It's the current that overheats wiring and connectors, not voltage.

Now it could have been a corroded connector that's caused voltage drop and so the current draw has increased. However, I would be cautious as to why it melted in the first place, jump starting a motorcycle from a car is fine. Running or otherwise.



Please don't ever try jump starting a car from a motorcycle though!!!!!



So a faulty battery could cause a increase in current and melt wire/connector?


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[Yellow650Loz]

So a faulty battery could cause a increase in current and melt wire/connector?


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Not ordinarily...... the charge system would compensate for the low output. Unless the reg/rec was burnt out too, or the stator. That would provide a scenario where common voltage could drop so far.
That being said, I've never known a faulty stator/Reggie rec/battery to melt wiring, not on it's own.
From what I've read .... yes I've skipped through a little.

You've got more than 70VAC between the pins from the stator resistance between pins is between 0.2 - 0.5

You tested the reg rec and found a dead diode, as the system wasn't charging properly it will have killed the battery.


Which wire was melted, was it?

White/bl stripe
Black/wh stripe
Red

[Bibio]

I think there's a few here mistaking voltage for current.
If the voltage drops then the current draw will be higher.

I.e.

55w @ 12V DC = 4.583 Amps
That's basically one headlamp bulb on a battery and engine off

55w @ 14.9V DC = 3.691 Amps
That's the same bulb but this time the battery is charging....the engine is running.

It's the current that overheats wiring and connectors, not voltage.
Now it could have been a corroded connector that's caused voltage drop and so the current draw has increased. However, I would be cautious as to why it melted in the first place, jump starting a motorcycle from a car is fine. Running or otherwise.

Please don't ever try jump starting a car from a motorcycle though!!!!!

100% correct. but its easier to get people to check problems using voltage without adding ohms law into the equation.

it would be nice to have a proper electrical/electronics expert on the forum.

[SV650rules]

as long as all three outputs are the same and MORE than 70VAC and less than 90VAC you have a healthy stator.

the more voltage the stator kicks out the more the regulator has to work so produces a little more heat.

contrary to popular belief its actually bad to run the bike without your lights on. you want to use as much power as you can without sacrificing charging/ignition system. once a battery is fully charged it should only need a trickle from the RR to keep it healthy.

+1


Any power the stator is producing that is not being used (loading up the system will reduce stator voltage) will have to be dumped by R/R and the only way it can dump this is by means of heat. Also as R1ffRAff has said many times any corrosion on R/R terminals will cause higher resistance and turn current flowing through the terminals into heat. This is a vicious circle = the hotter the terminals get the more they corrode - the more they corrode the higher the resistance gets and the hotter they get, this heat is conducted back into R/R and its components can get into thermal runaway - the diodes no longer block like they should and fail, and solid state bits like diodes always fail to a short circuit condition ( they conduct power when they should not) the only hope is that the wire connecting diode fails like a fuse - otherwise other things get taken out .

A car alternator works in a different way to the one on a motorbike, the car alternator has a coil on the rotor that gets excitation power via brushes and sliprings (very low current) - the power output of the alternator can be controlled relative to demand by increasing or reducing the magnetic field produced by the rotor coil. A motorbike alternator is really a pretty dumb bit of kit that just churns out power, and if this power is not used it has to be dumped by R/R in the form of heat.

I think there's a few here mistaking voltage for current.
If the voltage drops then the current draw will be higher.

I.e.

55w @ 12V DC = 4.583 Amps
That's basically one headlamp bulb on a battery and engine off

55w @ 14.9V DC = 3.691 Amps
That's the same bulb but this time the battery is charging....the engine is running.

It's the current that overheats wiring and connectors, not voltage.
Now it could have been a corroded connector that's caused voltage drop and so the current draw has increased. However, I would be cautious as to why it melted in the first place, jump starting a motorcycle from a car is fine. Running or otherwise.

Please don't ever try jump starting a car from a motorcycle though!!!!!

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A bulb may be a bad example because they are non-linear and resistance changes as filament temperature changes https://www.eetimes.com/author.asp?section_id=36&doc_id=1331961 - when power is first applied a filament bulbs draws an 'inrush current' many times greater than its running current, this is because with a cold filament the resistance is much lower than with a hot filament (reason why most bulbs blow when power is first switched on rather than when they are hot). The reason why a filament bulb in your house can trip the circuit breaker when it blows is that once the filament breaks it causes an electric arc to form, the resistance of the arc is very low compared to filament and so a lot of current can flow.

If the 55 watt bulb is replace with a standard resistor with fairly flat resistance / temperature characteristics then as the voltage increases the current flowing will increase in direct proportion to applied voltage. Once you quote a wattage then things change because a 55watt bulb designed to work at 6v will have to have half the resistance to allow double the current to flow than the same bulb designed to work at 12volts.

If a connector gets corroded it will cause higher resistance which will try to make current drop, but the problem is that as the voltage across the connector increases this will increase the heating effect on that connector, which with a very small area to dissipate the temperature quickly builds up, and flows back into parts of RR that do not contact heatsink, if added to this the RR is trying to compensate by maintaining a certain voltage at its terminals and voltage drop across external connector means RR will try to compensate by increasing voltage.

[Yellow650Loz]

100% correct. but its easier to get people to check problems using voltage without adding ohms law into the equation.

it would be nice to have a proper electrical/electronics expert on the forum.

Hmmm, if they're competent enough to tinker then they should understand what they're tinkering with. Afterall, were only trained by experience anyway.
It's a simple enough principal, it's the diagnostic that takes the brain power but that's why the OP is here anyway for diagnostic advice...

I couldn't call myself an expert anything, more of a Jack of all trades. Thanks though :cool: that did my ego a boost :D
Seriously though, I'm just happy to ward off the scrap heap for as many older vehicles as possible along the way.
I learn something new with every (New to me) bike car or lorry

I wasn't referring to you in the post about the confused voltage/current thing. You've been spot on

[Yellow650Loz]

Any power the stator is producing that is not being used (loading up the system will reduce stator voltage) will have to be dumped by R/R and the only way it can dump this is by means of heat.

Spot on

Also as R1ffRAff has said many times any corrosion on R/R terminals will cause higher resistance and turn current flowing through the terminals into heat. This is a vicious circle = the hotter the terminals get the more they corrode - the more they corrode the higher the resistance gets and the hotter they get,

Also spot on

this heat is conducted back into R/R and its components

The increased current draw from the R/R will result in less wasted. Generally; as you've said the more current to waste the hotter the R/R runs meaning a higher current draw will result in a cooler R/R.
The amount of heat "conducted" back through a vehicle wiring system is so miniscule it's not worth mentioning.....

A bulb may be a bad example because they are non-linear and resistance changes as filament temperature changes

Correct, as the temperature increases the resistance increases, just as with wiring, starter motors, coil packs, pumps even resistors
The reason this was used as an example is because in real world scenarios we will rarely see a random resistor drawing that many watts apart from heater blower motors, bulbs are very common for all the obvious reasons

- when power is first applied a filament bulbs draws an 'inrush current' many times greater than its running current, this is because with a cold filament the resistance is much lower than with a hot filament (reason why most bulbs blow when power is first switched on rather than when they are hot).

Yup, it's called peak current draw and then nominal current draw.
In my experience however, (600-1000 miles a week in a lorry) bulbs tend to fail due to harsh bumps....hot filament, quick jolt from a bump and the almost molten tungsten let's go.

The reason why a filament bulb in your house can trip the circuit breaker when it blows is that once the filament breaks it causes an electric arc to form, the resistance of the arc is very low compared to filament and so a lot of current can flow.

AC and DC work differently, with an AC system we deal with higher voltages in order to use solid core wherever possible. Electrons move over the outside of conductors with only a few exceptions and so the surface area is greatly reduced, thus can handle a lower current.
AC has more of a tendancy to arc due to the magnetic field created, I won't go too far into this as it isn't relevant to the OP, the first discharge lamps were DC and VERY unreliable due to the high current required to create the arc, AC ballasts are far more reliable and so the lower current draw is far more forgiving on it's components, especially within the discharge capsule.

If the 55 watt bulb is replace with a standard resistor with fairly flat resistance / temperature characteristics

I presume you mean using a resistor with 5% tolerance.....one with a gold band?

then as the voltage increases the current flowing will increase in direct proportion to applied voltage.

The current will only increase if there is a current draw......I.e. a bulb, motor, heating element ect. Increasing the voltage will only serve to apply more or less voltage to the device in question.

Once you quote a wattage then things change because a 55watt bulb designed to work at 6v will have to have half the resistance to allow double the current to flow than the same bulb designed to work at 12volts.

Spot on

If a connector gets corroded it will cause higher resistance which will try to make current drop, but the problem is that as the voltage across the connector increases this will increase the heating effect on that connector, which with a very small area to dissipate the temperature quickly builds up, and flows back into parts of RR that do not contact heatsink, if added to this the RR is trying to compensate by maintaining a certain voltage at its terminals and voltage drop across external connector means RR will try to compensate by increasing voltage.

You had so much right and changed your mind for the summary :smt017
If a connector gets corroded it will cause a higher resistance.....this will drop the VOLTAGE at the load which will increase the current drawn......please see ohms law for ref.
As the current increases this will increase the temperature of the corroded connector and further increase the resistance.
The amount of heat that can be physically conducted back to the R/R is miniscule. I won't say it can't be conducted back but if I heat just the tip of a length of say 14AWG wire to solder to, or get it cherry red.....20CM away from that point will be ambient or close to. Either way it's negligible. Consider that diodes are generally ok just over 70 deg c, if they weren't then the processor I'm your computer would fail about 10 seconds after switching on.
Having said that, as the old proverb goes. A candle that burns twice as bright lasts only half as long; yes, the hotter something runs, it's working lifespan will be reduced but we're talking about an R/R it's designed to run that hot.
The R/R is doesn't try to compensate, if the voltage drops below 13.5vdc with the lamps on high beam at 5000rpm then it's out of spec; or the charge systems components are unsuitable for the current load required. This is the reason the stator was upgraded on the injection bikes to circa 300w IIRC ...... Its got more electrics to run and therefore more load. The only thing it will do is stop feeding so much current and waste this off as heat.


I lost the quote bubbles somewhere along the way so I've underlined my annotations, perhaps if I ask very nicely....a mod might clean it up for me :D

SV650rules I hope this helps you as well as the OP or anyone in the future reading this thread.

[Yellow650Loz]

With DC they use the whole conductor, with AC; the higher the frequency the more they migrate towards the surface skin of the conductor.

Someone was listening in their physics lessons :cool:
In practice though, theres no such thing as a perfect conductor.
Yeah, as the frequency increases the charge density increases and the electrons are observed at the surface of a 'Perfect' conductor.
However in DC vehicle applications we use stranded 'flex' as this increases the total surface volume, reducing the need for massive solid core cables. Obviously there's the requirement for it to be flexible also.
I love a good physics discussion, but it doesn't help the OP :rolleyes:

[SV650rules]

You had so much right and changed your mind for the summary file:///C:\Users\Comet\AppData\Local\Temp\msohtmlclip1\01\ clip_image001.gif
If a connector gets corroded it will cause a higher resistance.....this will drop the VOLTAGE at the load which will increase the current drawn......please see ohms law for ref.
As the current increases this will increase the temperature of the corroded connector and further increase the resistance.
The amount of heat that can be physically conducted back to the R/R is miniscule. I won't say it can't be conducted back but if I heat just the tip of a length of say 14AWG wire to solder to, or get it cherry red.....20CM away from that point will be ambient or close to. Either way it's negligible. Consider that diodes are generally ok just over 70 deg c, if they weren't then the processor I'm your computer would fail about 10 seconds after switching on.
Having said that, as the old proverb goes. A candle that burns twice as bright lasts only half as long; yes, the hotter something runs, it's working lifespan will be reduced but we're talking about an R/R it's designed to run that hot.
The R/R is doesn't try to compensate, if the voltage drops below 13.5vdc with the lamps on high beam at 5000rpm then it's out of spec; or the charge systems components are unsuitable for the current load required. This is the reason the stator was upgraded on the injection bikes to circa 300w IIRC ...... Its got more electrics to run and therefore more load. The only thing it will do is stop feeding so much current and waste this off as heat.


I lost the quote bubbles somewhere along the way so I've underlined my annotations, perhaps if I ask very nicely....a mod might clean it up for me file:///C:\Users\Comet\AppData\Local\Temp\msohtmlclip1\01\ clip_image002.gif

SV650rules I hope this helps you as well as the OP or anyone in the future reading this thread.
Not helped at all…………………….
You are having a laff right ? if you increase resistance anywhere in a circuit and voltage stays the same current is always going to drop (see Ohms law I = V/R if the numerator stays the same (V) and the denominator gets larger (R) the value of result (I) has to get smaller. You are making the mistake of keeping the 'wattage' at the load at eg 55watt, and sure enough to maintain 55watt at a lower voltage the current would have to increase (W-V*I) but as the voltage drops that 55watt bulb will just get dimmer, and while the number on the bulb may still say 55watt the bulb will not produce 55 watt of light because it is designed to be 55watt at 12.5 volts.




AC and DC work differently, with an AC system we deal with higher voltages in order to use solid core wherever possible. Electrons move over the outside of conductors with only a few exceptions and so the surface area is greatly reduced, thus can handle a lower current.
AC has more of a tendancy to arc due to the magnetic field created, I won't go too far into this as it isn't relevant to the OP, the first discharge lamps were DC and VERY unreliable due to the high current required to create the arc, AC ballasts are far more reliable and so the lower current draw is far more forgiving on it's components, especially within the discharge capsule.

If the 55 watt bulb is replace with a standard resistor with fairly flat resistance / temperature characteristics

I presume you mean using a resistor with 5% tolerance.....one with a gold band?



It is only at pretty high frequency you get a ‘pipe’ effect with electrons where they tend to use outside of conductor, at 50Hz no probelmo ( they use solid core cable for normal domestic wiring). The reason a solid core is used in house wiring and not in machinery and vehicles is that solid cores tend to break when they are subject to movement and vibration, where stranded ‘flexibles’ do not’.

The tolerance of a resistor has nothing to do with whether it has a low or a high positive or negative coefficient of resistance, it is all down to what it is made from – when I said a standard resistor it was ‘a standard resistor that is designed (as they are) to not change resistance much as it got hotter or cooler’ (which is the opposite of a bulb filament the resistance of which changes massively as it heats up).

Actually DC has more of a tendency to arc than AC, simply because an sine wave (AC) passes through zero volts once every half cycle ( every 10mSec at 50 Hz) as it transitions from positive to negative – this will quench any arc (an arc cannot exist without voltage), DC only passes through zero volts when it is turned off, so once an arc is established there is nothing to quench it.

[Yellow650Loz]

Not helped at all…………………….
You are having a laff right ? if you increase resistance anywhere in a circuit and voltage stays the same current is always going to drop (see Ohms law I = V/R if the numerator stays the same (V) and the denominator gets larger (R) the value of result (I) has to get smaller. You are making the mistake of keeping the 'wattage' at the load at eg 55watt, and sure enough to maintain 55watt at a lower voltage the current would have to increase (W-V*I) but as the voltage drops that 55watt bulb will just get dimmer, and while the number on the bulb may still say 55watt the bulb will not produce 55 watt of light because it is designed to be 55watt at 12.5 volts.


Might I suggest you're beyond help then :smt102
If you increase the resistance in a circuit the voltage will drop. This isn't a textbook mate, the drop in voltage will cause a higher current draw.
It's 55w nominal, that's what it's rated at...... you're struggling to get this, I won't keep explaining how this all works in the real world. When you mess up the electrics on yours, let me know....I'll buy it :smt038




It is only at pretty high frequency you get a ‘pipe’ effect with electrons where they tend to use outside of conductor, at 50Hz no probelmo ( they use solid core cable for normal domestic wiring). The reason a solid core is used in house wiring and not in machinery and vehicles is that solid cores tend to break when they are subject to movement and vibration, where stranded ‘flexibles’ do not’.

The tolerance of a resistor has nothing to do with whether it has a low or a high positive or negative coefficient of resistance, it is all down to what it is made from – when I said a standard resistor it was ‘a standard resistor that is designed (as they are) to not change resistance much as it got hotter or cooler’ (which is the opposite of a bulb filament the resistance of which changes massively as it heats up).

Actually DC has more of a tendency to arc than AC, simply because an sine wave (AC) passes through zero volts once every half cycle ( every 10mSec at 50 Hz) as it transitions from positive to negative – this will quench any arc (an arc cannot exist without voltage), DC only passes through zero volts when it is turned off, so once an arc is established there is nothing to quench it.

Again, I won't repeat what I wrote. I have a job to do :cool:

[SV650rules]

@Yellow650Loz

https://www.amazon.co.uk/Basic-Electricity-Self-Teaching-Guide-Guides/dp/0471850853

[daktulos]

If you increase the resistance in a circuit the voltage will drop. This isn't a textbook mate, the drop in voltage will cause a higher current draw.

I'm not sure where you've got this from, if the voltage across a (relatively) fixed resistance load drops, the current will also drop.

With a corroded connection, it's effectively an additional load in the circuit. Because of this, there's a voltage drop across it and therefore power consumed which must be dissipated as heat.

The easiest way to diagnose a problem is to check the voltages between the battery, R/R and load and either side of connectors between. In a perfect world they should all be the same. If there's a significant difference between any two, then your problem will be between the two points. The Haynes manual (if I remember correctly) gives acceptable voltage differences.

The same applies to the earth. A garage once needlessly replaced the starter motor on my car because they swore it was dead as they could see a voltage on it. It turned out that the earth bonding was shot and it was just the clutch cable providing a path back to the battery -ve.

[glang]

I wonder if some of the confusion is coming from this: Although simple electrical items like lights, heaters etc consume less current with a lower voltage across their terminals some more complicated items like induction motors do actually draw more amps to maintain their power output.

[Yellow650Loz]

I'm not sure where you've got this from, if the voltage across a (relatively) fixed resistance load drops, the current will also drop.

With a corroded connection, it's effectively an additional load in the circuit. Because of this, there's a voltage drop across it and therefore power consumed which must be dissipated as heat.

The easiest way to diagnose a problem is to check the voltages between the battery, R/R and load and either side of connectors between. In a perfect world they should all be the same. If there's a significant difference between any two, then your problem will be between the two points. The Haynes manual (if I remember correctly) gives acceptable voltage differences.

The same applies to the earth. A garage once needlessly replaced the starter motor on my car because they swore it was dead as they could see a voltage on it. It turned out that the earth bonding was shot and it was just the clutch cable providing a path back to the battery -ve.


you've just said the same thing, It's effectively an additional load on the system. However it also creates a problem on both sides, the component being supplied the power in the first place will have a reduction in voltage.
It's rated at 12v however Suzuki designed the system and the wiring to run at 13.8v curvy or 14.9 pointy IIRC.

Im sure the OP said a starter motor was used alot; because the bike wouldn't start, it would start to overheat the circuit, it's not designed to be used like that, eventually the weak link would be found. In this case the connector. Was the connector actually found to be rusty? Or just melted? I can't remember or mustav skipped that page :compcrash:

[SV650rules]

I'm not sure where you've got this from, if the voltage across a (relatively) fixed resistance load drops, the current will also drop.

With a corroded connection, it's effectively an additional load in the circuit. Because of this, there's a voltage drop across it and therefore power consumed which must be dissipated as heat.

The easiest way to diagnose a problem is to check the voltages between the battery, R/R and load and either side of connectors between. In a perfect world they should all be the same. If there's a significant difference between any two, then your problem will be between the two points. The Haynes manual (if I remember correctly) gives acceptable voltage differences.

The same applies to the earth. A garage once needlessly replaced the starter motor on my car because they swore it was dead as they could see a voltage on it. It turned out that the earth bonding was shot and it was just the clutch cable providing a path back to the battery -ve.

+1

Although the corroded connector should probably be described as 'an extra resistance' rather than 'an extra load' - but I understand that you mean a load in the sense that work is being done at that point by the current flow, the unwanted resistance caused by corrosion of the contact faces will cause extra work (heat) at that point. Second law of thermodynamics basically says 'All energy ends up as heat'

On every car I have owned I have fitted one of these braided leads between battery negative terminal and engine block, I do not trust all those small rusty connections between body and engine...

https://www.halfords.com/webapp/wcs/stores/servlet/SearchRouter?langId=-1&storeId=10001&catalogId=10151&action=search&srch=earth+braid