Multimeter results for stator test

[rhyatt]

You have a 2 wire stator we know , but is this a brand new stator with 2 yellows coming out of it.

Or

Has a PO fitted a 2 wire 12volt lucas encapsulated stator

Or

Has a PO modified an original 6 volt 3 wire stator by joining a certain pair of wires together to convert a 6v into 12v

I ask this because the original 3 wire stator had green/green yellow/green white coming from the stator.
And my 12v lucas 2 wire stator had similar colours coming out of its encapsulated stator

[Derek996]

In his first post KevD states that the bike is fitted with an Electrex STK-100DC alternator/igntion system. This has a 2 wire alternator for charging and an independent CDI igntion system.
This is the wiring diagram below. For positive earth it it much the same except the battery connections are reversed.

[rhyatt]

looking a bit deeper into this issue and I find this diagram which is clearly showing your kit---

https://www.dropbox.com/scl/fi/hpbo35ld32zbakn5it352/STK-100D.pdf?rlkey=z8m3sb5yo4jacimsv4wi4s5j6&e=1&dl=0

a 5 wire stator (their own unique one) with 2 yellows going into their RR02 reg/rec

Is this how your bike is wired up ?

the AC principle still stands - namely AC with you meter across their 2 yellows - yes or no AC output -- mustn't involve earth or anything

you could try 20 or 200 ohms scale and look INTO the stator to see if there is continuity inside the yellow windings

[Kev D]

looking a bit deeper into this issue and I find this diagram which is clearly showing your kit---

https://www.dropbox.com/scl/fi/hpbo35ld32zbakn5it352/STK-100D.pdf?rlkey=z8m3sb5yo4jacimsv4wi4s5j6&e=1&dl=0

a 5 wire stator (their own unique one) with 2 yellows going into their RR02 reg/rec

Is this how your bike is wired up ?

the AC principle still stands - namely AC with you meter across their 2 yellows - yes or no AC output -- mustn't involve earth or anything

you could try 20 or 200 ohms scale and look INTO the stator to see if there is continuity inside the yellow windings

Yes that's  how my bike is wired ,except it's  positive earth.

[rhyatt]

ok , then if it is not charging , which i think is the issue , it can only be 3 sources--
1 no AC coming out of the 2 yellow stator wires
2 you have AC at 1 but the RR is not doing anything with it and sending DC to the battery
3 a wiring issue

[Kev D]

ok , then if it is not charging , which i think is the issue , it can only be 3 sources--
1 no AC coming out of the 2 yellow stator wires
2 you have AC at 1 but the RR is not doing anything with it and sending DC to the battery
3 a wiring issue

The initial investigation  started when l had no charge at the battery.

I (eventually)discovered that where the two yellow stator wires had been extended the joints were left uninsulated and were touching due to being bound together by the loom tape.
I separated these and insulated them from each other

I seem to have have AC from only one yellow stator wire but the battery is showing some charge now.
I went for a ride this afternoon with the lights on and the battery stayed charged!

The sketch shows what were  the two uninsulated joints. Possibly the PO forgot to slide the plastic insulators over them before wrapping them in loom tape .
.

But would this unintended  connection between the yellow stator wires have caused my problem?

Or indeed damaged the stator?

I really appreciate  everyone's  patience in helping me .
Kev

[rhyatt]

that's good news if it is charging now
basic checks on voltages should be thus--
ignition off / lights off everything off , battery should show around 12.5 ish DC volts across its 2 + and - terminals

then running should bring the voltages across the battery up to around 14 DC volts ( ideally 14.2 ish)

BUT
a flattish battery will by definition , show a lower than 14 volts due to it absorbing some of the incoming charge until it eventually reaches 14.2 , then the regulator cuts off the incoming charge and dumps the surplus to earth in the form of heat(hence the finned body)

always conduct charging check on a fully charged battery obviates this "delay" period

a slightly longer ride with lights off and a volts check when you get home hopefully shows you 14 V dc

But would this unintended  connection between the yellow stator wires have caused my problem?
absolutely - a shorting of the AC output will limit/negate what is going into the RR

damage to the stator- only time and the above volts checks will show you

as an aside , I had a RR that proved to be faulty by way of the internal diodes failing - it meant that the battery was discharging backwards through the RR diode into the stator winding and making the stator into an electro-magnet and trying to rotate the rotor/crank - took me a while to diagnose that !!

[limeyrob]

I think all you can do it ride it and see how it performs over a few weeks.  The short could have done damage but not necessarily, its hard to know.  If its charging, the lights are working, its not misfiring then indications are good but check the battery is not over gassing and if you get bulbs blowing there is probably a problem.

[V500]

if the two yellows have shorted together it shouldn't have caused any problems as these simple alternators don't generate "into" a fault. The stator merely becomes a loop of wire with a magnet rotating within it.

[Kev D]

that's good news if it is charging now
basic checks on voltages should be thus--
ignition off / lights off everything off , battery should show around 12.5 ish DC volts across its 2 + and - terminals

then running should bring the voltages across the battery up to around 14 DC volts ( ideally 14.2 ish)

BUT
a flattish battery will by definition , show a lower than 14 volts due to it absorbing some of the incoming charge until it eventually reaches 14.2 , then the regulator cuts off the incoming charge and dumps the surplus to earth in the form of heat(hence the finned body)

always conduct charging check on a fully charged battery obviates this "delay" period

a slightly longer ride with lights off and a volts check when you get home hopefully shows you 14 V dc

But would this unintended  connection between the yellow stator wires have caused my problem?
absolutely - a shorting of the AC output will limit/negate what is going into the RR

damage to the stator- only time and the above volts checks will show you

as an aside , I had a RR that proved to be faulty by way of the internal diodes failing - it meant that the battery was discharging backwards through the RR diode into the stator winding and making the stator into an electro-magnet and trying to rotate the rotor/crank - took me a while to diagnose that !!

Rhyatt. Thank you for your patience and advice. As you say time (and a volt test) will tell . Thanks again.

I think all you can do it ride it and see how it performs over a few weeks.  The short could have done damage but not necessarily, its hard to know.  If its charging, the lights are working, its not misfiring then indications are good but check the battery is not over gassing and if you get bulbs blowing there is probably a problem.

limeyrob. Thank you. Sounds like a good excuse to put a few more running- in miles on the bike . I did notice a couple of really tiny glitchy misfires that felt electrical( if that makes sense) in the first hundred yards when l went out yesterday but nothing after that.l took the long route to a local bike show   .

 When l left a few hours later the bike started first kick( which saved me embarrassment  in front of my mates and some rather hairy be-patched onlookers)and ran well on the way home .My fingers are so crossed they are knotted .

So far so good but if anything naughty shows up l have an idea of where to look.
 
 Thanks to everybody who has chipped-in .
    Kev