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Welcome to the new B.I.R.D. Forum. Please be sure to read the "New Member / New Registered ? Please Read" thread in the Coffee Shop. This contains some important information. To become a full member ( £5.90 a year ) simply click on your user name near the top on the right I hope you enjoy the new site ................ Jaws ( John )
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bishbosh
Guest
I'm in Llandybie near Ammanford so have done a run from West End Cafe Llandovery up to Aber plenty of times so when bike's back working will come up for a spin.
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bishbosh
Guest
Right then, still no joy arrrgh.
New battery - bike starts ok
New RegRec ?
New Stator - each par getting 45v ac @ 3000 rpm, 75-80v ac @5000 rpm
Had a look around and there was a diode test you can do on the RegRec
So here are my figures on the new RegRec
Neg probe to Red/White terminal
Pos probe to Alt terminals
0.553 0.558 0.555
Pos probe to Earth terminal
Neg probe to Alt terminals
0.554 0.554 0.554
There are some variations on the top readings, don't know if that is significant, would like to see what the readings are from a know working unit.
New battery - bike starts ok
New RegRec ?
New Stator - each par getting 45v ac @ 3000 rpm, 75-80v ac @5000 rpm
Had a look around and there was a diode test you can do on the RegRec
So here are my figures on the new RegRec
Neg probe to Red/White terminal
Pos probe to Alt terminals
0.553 0.558 0.555
Pos probe to Earth terminal
Neg probe to Alt terminals
0.554 0.554 0.554
There are some variations on the top readings, don't know if that is significant, would like to see what the readings are from a know working unit.
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bishbosh
Guest
no, not yet, should get a chance tomorrow. ta.
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bishbosh
Guest
Oh dear, seems we have AC voltage from all three Alternator terminals to earth.
Readings were same for all three terminals give or take.
14 ac @1800 rpm (with choke out)
8v ac @1100 rpm (tickover)
So what does that mean?
Interestingly though I had a couple of ac volts showing on meter with just the positive probe in the terminal block without the negative terminal touching anything, but then when touched earth got the readings above.
Readings were same for all three terminals give or take.
14 ac @1800 rpm (with choke out)
8v ac @1100 rpm (tickover)
So what does that mean?
Interestingly though I had a couple of ac volts showing on meter with just the positive probe in the terminal block without the negative terminal touching anything, but then when touched earth got the readings above.
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bishbosh
Guest
Well good news is you have now found the fault..
The bad news is two fold
1) You need a new genny
2) You shoulda taken note of my post on the 4th !!8rfl@
Yeah I know, head in the clouds!!
Genny - as opposed to the stator, you mean the spinny thing?
I've fitted a new stator.
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bishbosh
Guest
So what is causing there to be AC voltage back through the frame and where is it going?
Is there a short somewhere with the flywheel, could it be touching the stator?
One last thing, I tested the AC voltage at the RegRec connector, do you think there's a chance the fault is in the loom and I should recheck with the alternator connector or was this test not showing up a loom issue?
Is there a short somewhere with the flywheel, could it be touching the stator?
One last thing, I tested the AC voltage at the RegRec connector, do you think there's a chance the fault is in the loom and I should recheck with the alternator connector or was this test not showing up a loom issue?
Basically yes, there is a leak to earth somewhere.. It is usually a breakdown of the insulation lacquer in one of the coils :xm
This is far from a rare fault.. It is in fact the second most common.
You can check all sorts but the chances of it being anything but the genny is pretty remote
Errr.. re-reading your post..
You did do the test with the plug unplugged didn't you ?
This is far from a rare fault.. It is in fact the second most common.
You can check all sorts but the chances of it being anything but the genny is pretty remote
Errr.. re-reading your post..
You did do the test with the plug unplugged didn't you ?
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bishbosh
Guest
Yes, tested with plug unplugged, and just to reiterate the genny is new so could there be a short in that?
If not the genny and with a short somewhere in the system, it must be somewhere else. The stator should be isolated by an air gap to the flywheel and the cover by the gasket; wonder if it's the steel replacement bolts for the cover so they are connecting the cover back to engine casing.
Should I have no continuity between bolts/cover back to earth.
Or are the windings on the stator isolated to the genny block itself?
Nope.. I would say that when the genny was fitted something snagged on a coil breaking the insulation down.:xm
If you checked it with the plug unplugged then you have isolated the genny completely from the rest of the bike so have removed all guesswork from the equation .
Basically there are only three components to the whole system
The genny, the reg rec and the battery
The wiring does directly between each component.. It is a VERY simple circuit.
If you checked it with the plug unplugged then you have isolated the genny completely from the rest of the bike so have removed all guesswork from the equation .
Basically there are only three components to the whole system
The genny, the reg rec and the battery
The wiring does directly between each component.. It is a VERY simple circuit.
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bishbosh
Guest
Is there any way to perform a static test for that, there is no continuity between the pairs of wires.
No.. not really.
I did have a couple of thoughts..
1) Try another meter to confirm readings
Some meters have such a low resistance they give false readings on AC more or less picking stuff out of thin air ( induction )
2) there is a forth component to the system.. A purely mechanical one
Check very carefully the connections on top of the starter solenoid
I did have a couple of thoughts..
1) Try another meter to confirm readings
Some meters have such a low resistance they give false readings on AC more or less picking stuff out of thin air ( induction )
2) there is a forth component to the system.. A purely mechanical one
Check very carefully the connections on top of the starter solenoid
Just to clarify Bishbosh.
A genius discovered a century plus ago that if a wire was moved through a magnetic field then a voltage was created. The stronger the magnetic field and the faster the movement the higher the voltage. Multiple windings rather than a single wire also generated more voltage. In a bike alternator we keep the windings static and move the magnet. Same effect. More revs equals more voltage. Your bike alternator is three phase as it has three winding sections of six coils each at 120 degrees spacing. Each winding section is joined at one end to the other two but crucially all three are insulated from the bikes earth. If you checked the voltage between each phase and earth and got a reading with the alternator unplugged then at least one part of one of the windings is shorted to earth. It is likely as Jaws said that during fitting the varnish on a winding was scratched and bare wire is touching metal. Usually underneath. If you remove the alternator and look carefully you may see the damage. Replacing the alternator (again) is the only real option. I have repaired a damaged stator coil but it's a bit of a bodge I wouldn't like to depend on. As they say in Ireland I'm sorry for your troubles. :-0) The drawing is simplified but note that if you disconnect the alternator plug with the three yellow? wires then there is no connection to earth so no voltage should be measured between any of the yellow wires and earth. If you can measure a voltage then a winding is shorting to the engine.
A genius discovered a century plus ago that if a wire was moved through a magnetic field then a voltage was created. The stronger the magnetic field and the faster the movement the higher the voltage. Multiple windings rather than a single wire also generated more voltage. In a bike alternator we keep the windings static and move the magnet. Same effect. More revs equals more voltage. Your bike alternator is three phase as it has three winding sections of six coils each at 120 degrees spacing. Each winding section is joined at one end to the other two but crucially all three are insulated from the bikes earth. If you checked the voltage between each phase and earth and got a reading with the alternator unplugged then at least one part of one of the windings is shorted to earth. It is likely as Jaws said that during fitting the varnish on a winding was scratched and bare wire is touching metal. Usually underneath. If you remove the alternator and look carefully you may see the damage. Replacing the alternator (again) is the only real option. I have repaired a damaged stator coil but it's a bit of a bodge I wouldn't like to depend on. As they say in Ireland I'm sorry for your troubles. :-0) The drawing is simplified but note that if you disconnect the alternator plug with the three yellow? wires then there is no connection to earth so no voltage should be measured between any of the yellow wires and earth. If you can measure a voltage then a winding is shorting to the engine.
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bishbosh
Guest
Well I'll remove the stator and check, have fitted half a dozen and pretty sure I fitted it neatly, but don't discount it obviously.
The static test didn't show any continuity between the connector block and earth but I guess that is a very small amount of volts trying to make the jump.
What about connecting my old 12v battery (replaced as didn't have enough umph - technical term) to a pin on the connector block and then a volt meter between the other pole and earth? If the stator is insulated you won't have a circuit, but if broken then should show some reading. I also have soldered a couple of wires to a 1.7w 12v dash bulb to test for presence of volts as sometimes a specific reading is not required.
The static test didn't show any continuity between the connector block and earth but I guess that is a very small amount of volts trying to make the jump.
What about connecting my old 12v battery (replaced as didn't have enough umph - technical term) to a pin on the connector block and then a volt meter between the other pole and earth? If the stator is insulated you won't have a circuit, but if broken then should show some reading. I also have soldered a couple of wires to a 1.7w 12v dash bulb to test for presence of volts as sometimes a specific reading is not required.
The only sure test is voltage between yellow wires with the plug undone from reg/rec. Any AC voltage means the alternator is shorting to earth. A bulb designed to use 12v DC will not light up with low AC voltage, BB. Do you not trust your meter?