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Discussion Starter #1
Hi all.

I went out for a 20 mile ride yesterday, got back, stopped the bike to get the garage door up, went to restart her and 2 cranks and clicking so battery nearly discharged. Charge the battery overnight, put it back on the bike and, obviously, fired up staraight away. Then I tested the battery with a multi-meter and showed 12.4v. Started the bike and while cranking went to 10.2v which tells me that the battery is in fairly good health. Ran the bike around 2000RPM and the voltage was just over 13v. More RPM and the voltage dropped to low 12v which seems odd to me as my llogic tells me that it should go up?

The puzzling bit is that the battery had lost its charge AFTER a run:surprise: (I have a relay to enable both dip beams all of the time fitted. I've tested with and without the relay but hardly makes any difference.

Does anyone have a clue as to what is happening.

Thanks folks.

Jon
 

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Discussion Starter #3
UPDATE

UPDATE

Just checked the stator voltages. The connector to the rectifier was pretty melted and the spade connectors came out when i pulled the connector. Checked the three phase terminals from the stator anyway and absolutely no reading on any of them. Am I correct in assuming that the stator is the culprit?
 

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To check the stator, simply disconnect and measure resistance from any one terminal to engine ground - if this is 'short' (zero or close to zero ohms) then stator is fried. If 'open' infinite resistance, is good.
That test is sufficient, no need to even check voltages.
However if you really feel you need to (and it has passed the resistance check - if not don't even bother!) then you set your meter to AC V and measure between the three possible combinations of two-pins. i.e. A-B, B-C, A-C - where AB & C are arbitrarily assigned as you choose.
You cannot get 'nothing' as even a failed stator will still produce voltage.

* bike not running nor even ignition on.

p.s. Please add your model year to your bike info in your profile
 

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Discussion Starter #6
I Know Steve. Not a cheap fix but has to be done. Looks like it has gone before as its not the first time that the cover has been off!
 

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Just set my model year DEcosse.

I checked the AC voltage coming to the 3 pins one by one with the engine running and absolutely nothing on the multi-meter! Doesnt look like the first time that the cover has been off either, so this has happened before. Can you suggest what to replace the stator with? An original Triumph one is silly money but I have found one on fleabay for @£130. Would you change the regulator too?
 

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Discussion Starter #10
Hi DEcosse.

That is how you explained. I did the resistance check with all 3 phases but 0 reading from each one. The plug had melted which made it a little tricky to disconnect but, nonetheless, there was no reading with the engine running.
 

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... I did the resistance check with all 3 phases but 0 reading from each one. ...
What does "0 reading" mean - zero ohms, or infinite resistance (where the reading on the meter is the same as if you did not connect probes to anything?

there was no reading with the engine running .....
Again, you said "I checked the AC voltage coming to the 3 pins one by one" .........

I said "set your meter to AC V and measure between the three possible combinations of two-pins. i.e. A-B, B-C, A-C - where AB & C are arbitrarily assigned as you choose"
Literally, that would be pair by pair - one by one infers you are checking each one terminal to ground - and if your stator passes the resistance isolation test, then indeed, you would not get a voltage reading between any ONE pin to ground.

Resistance check - any ONE pin to Ground
Voltage check - between any TWO pins.

And again
"You cannot get 'nothing' as even a failed stator will still produce voltage."

So you are definitely doing something wrong with how you are measuring. It is simply not possible to get zero voltage out - even a fried stator will still produce voltage, it will just be compromised on one phase (which will measure less volts than the other two, but still some. (except unless you are measuring incorrectly as described above.
 

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Discussion Starter #12 (Edited)
I did the resistance check and absolutely no reading at all. You'll see by the photos that the plug is well melted. There was a bit of sparking as the phase wires did touch which could have been the reason for the plug being melted. The stator doesn't look like its fried though, which I fully expected to see!
 

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Yes it seems fine.



Sorry but:

"I did the resistance check and absolutely no reading at all" is difficult to understand.


Either you get an infinite resistance (each coil isolated from the case/cover) or not. Most of the time when you get a resistance lower than infinite, it's directly 0 (short circuit) or close to (each coil has a very low resistance because of the big wire gauge).


Often, a numeric multi-meter measuring an infinite resistance is displaying a I (or 1) at the left of the display.
If it's an analogical one (w/ a needle) the needle won't move.


Regarding the spade connector you can either use separated spade connectors or get a triple one. EasternBeaver may have that.



Fred
 

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Discussion Starter #14
Hi Fred.

With the bike running at tick-over, I set the digital multi-meter to (see photo), connected black to battery ground and red to each connector in turn. No reading on any of the 3 phases. I made sure that they weren't touching each other also. I'm beginning to think i'm going mad, or just stupid!


Jon
 

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You need to cut that connector off and get to good clean copper - it's going to have to go regardless and your stator otherwise looks fine.
You simply can't be getting electrical contact with your probes. There's nothing salvageable in that connector, so just cut it off and get to good wire.

And again, echoing my earlier comments - and Fred's - you cannot say "I get no reading at all" on resistance - if you mean it is infinite - open circuit, you need to state that.
But given the image, it appears stator is fine anyway.

As said, you need to cut harness back till you get good un-oxidized copper wire. Then you can either install a new connector (if you do, be sure you have the correct crimp tool for the type of terminals being used and additionally solder it AFTER you crimp)
Or for a quick easy (even temporary) test, again, once you get good clear copper, you can use bullet crimps to connect the wires to the R/R harness.
 

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Hi Fred.

With the bike running at tick-over, I set the digital multi-meter to (see photo), connected black to battery ground and red to each connector in turn. No reading on any of the 3 phases. I made sure that they weren't touching each other also. I'm beginning to think i'm going mad, or just stupid!


Jon
It's not that you are stupid. It's just that you don't understand the technical part of it.


The stator is a three phases generator that produces alternative voltage (and current).
Each coil produces an alternative voltage that is shifted (dephased) by 1/3 third of an engine rotation.
To get direct voltage (and current) the RR contains a three phases rectifier (6 diodes arrangement).

So because of this the coils voltage is kind of "floating" most of the time. That means YOU CAN'T measure the coils voltage using the battery ground as a reference.


The only way to measure the coil voltage is to touch the black multimeter wire to one of the three coil wire and the red mutimeter wire to another coil wire. If you think a bit you'll understand (as DEcosse explained) that you have three combinations, so three measurement to perform.


Please note that the three coils are connected in a triangle fashion. That means there is no central point.


You got is right when you set the multimeter on alternative voltage though. The voltage ranges from 40V to ~200V (or more) at high rpm.


........................................



Obviously you get that measuring the voltage while running is a complete different story than measuring the resistance between the coils and the ground (while not running). Multimeter set on "resistance/Ohm" position (lower value position). As the coils are "floating" (see above), they are completely isolated from the steel used to make the magnetic core.



So NO CURRENT is flowing between the coils and the core. So when the coils are disconnected from the RR, the resistance measurement between each and every coil and the steel magnetic core (connected/in contact w/ the frame/case) would show NO CURRENT flowing hence showing an Infinite resistance.


Fred
 

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Discussion Starter #18
You need to cut that connector off and get to good clean copper - it's going to have to go regardless and your stator otherwise looks fine.
You simply can't be getting electrical contact with your probes. There's nothing salvageable in that connector, so just cut it off and get to good wire.

And again, echoing my earlier comments - and Fred's - you cannot say "I get no reading at all" on resistance - if you mean it is infinite - open circuit, you need to state that.
But given the image, it appears stator is fine anyway.

As said, you need to cut harness back till you get good un-oxidized copper wire. Then you can either install a new connector (if you do, be sure you have the correct crimp tool for the type of terminals being used and additionally solder it AFTER you crimp)
Or for a quick easy (even temporary) test, again, once you get good clear copper, you can use bullet crimps to connect the wires to the R/R harness.
You are, of course, correct. The connector needs to come off. I will do that and let you know the results but i'm sure that it must have been a bad connection heating the connector up, causing the plastic to melt.

Apologies for my terminology. I've never used a multimeter before so my meaning was that the digits didn't change when i touched any of the phases. It just read 00.0, which I took as no reading.

Thanks for staying with me on this.
 

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Discussion Starter #19
It's not that you are stupid. It's just that you don't understand the technical part of it.


The stator is a three phases generator that produces alternative voltage (and current).
Each coil produces an alternative voltage that is shifted (dephased) by 1/3 third of an engine rotation.
To get direct voltage (and current) the RR contains a three phases rectifier (6 diodes arrangement).

So because of this the coils voltage is kind of "floating" most of the time. That means YOU CAN'T measure the coils voltage using the battery ground as a reference.


The only way to measure the coil voltage is to touch the black multimeter wire to one of the three coil wire and the red mutimeter wire to another coil wire. If you think a bit you'll understand (as DEcosse explained) that you have three combinations, so three measurement to perform.


Please note that the three coils are connected in a triangle fashion. That means there is no central point.


You got is right when you set the multimeter on alternative voltage though. The voltage ranges from 40V to ~200V (or more) at high rpm.


........................................



Obviously you get that measuring the voltage while running is a complete different story than measuring the resistance between the coils and the ground (while not running). Multimeter set on "resistance/Ohm" position (lower value position). As the coils are "floating" (see above), they are completely isolated from the steel used to make the magnetic core.



So NO CURRENT is flowing between the coils and the core. So when the coils are disconnected from the RR, the resistance measurement between each and every coil and the steel magnetic core (connected/in contact w/ the frame/case) would show NO CURRENT flowing hence showing an Infinite resistance.


Fred
Thanks for the explanation Fred.

I'll keep you posted when I have reasembled it and tested it with the wires stripped back etc. I have ordered a gasket so am just waiting on that to arrive.
 

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Discussion Starter #20
Check multimeter against known good AC voltage supply.
Thanks Dibnah. It's a brand new multimeter but the first check that i did was on the battery and that was fine, allbeit a DC current. Where else would I check for an AC current? (excuse my ignorance - electrics have never been my strong point but, thanks to you guys on here, I am learning a lot)

Jon
 
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