GT380 Alternator Rotor Removal

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miked914
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Re: GT380 Alternator Rotor Removal

Post by miked914 »

I have the ground wire from the R/R tied directly into the Black/White ground wire that runs to the alternator body and am getting good ground both through that connection and when I test the RR body to ground as well.

What is the best way to test the R/R—I wonder if I have a bad one which is why I’m not getting any voltage coming out
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Alan H
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Re: GT380 Alternator Rotor Removal

Post by Alan H »

You'll not be able to check it as it is resin sealed. Check my earlier post regarding how it's plugged in colour to colour - exactly.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
miked914
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Re: GT380 Alternator Rotor Removal

Post by miked914 »

OK, Just going back over everything I have good ground to the RR and with the “Input” plug attached (3 yellow Stator Wires and the Red 12 Volt Power Wire) Im getting 0 volts at any of the 3 “Output” wires from the RR (Orange, Green or Black)

So, voltage is going IN, but nothing coming Out—is this a sign of a bad RR?
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jabcb
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Re: GT380 Alternator Rotor Removal

Post by jabcb »

My ESR770 has:
1) a voltage regulator plug with two wires (orange & green)
2) a rectifier plug with 4 wires (red & 3 yellow)
3) a separate black wire for ground

Does your voltage regulator plug has 3 wires (orange, green & black)?

For the rectifier plug:
1) the 3 yellow wires receive the alternator AC output.
2) the red wire is connected to the battery. It always reads roughly battery voltage. The red wire sends the alternator output to the battery.

For the voltage regulator plug:
1) the orange wire is switched power.
When the ignition switch is off, the voltage is zero.
When the ignition switch is on & the engine kill switch is on, then the orange wire is at near battery voltage.
2) the green wire sends power to the alternator rotor depending how much alternator output is needed.
When the orange wire is at 0V, the green wire is at 0V.
When the motor is not running & the orange wire is at near battery voltage, then the green wire has about the same voltage.

When the motor is running & the orange wire is at near battery voltage, then the green wire voltage varies with a maximum of up to the same voltage as the orange wire.



An easy check of the R/R:
1) connect the R/R ground wire to a good ground
2) connect the orange wire to the battery + terminal
3) measure the voltage at the green wire. You should get battery voltage.
When done, disconnect the orange wire.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
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Alan H
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Re: GT380 Alternator Rotor Removal

Post by Alan H »

miked914 wrote:OK, Just going back over everything I have good ground to the RR and with the “Input” plug attached (3 yellow Stator Wires and the Red 12 Volt Power Wire) Im getting 0 volts at any of the 3 “Output” wires from the RR (Orange, Green or Blacks
So, voltage is going IN, but nothing coming Out—is this a sign of a bad RR?
There appears to be some misunderstanding with the wiring here.

Small plug has 3 wires;
Black/white stripe - earth (the RR needs this to work). But will read 0 volts as it is from the bike earth circuit.

Orange - switched live IN - it needs this to work the whole shebang. (If there's nothing going in here, it can't do anything.) You should get battery voltage if you unplug this and test on DC volts into the orange and black/white in the SOCKET on the bike with ignition and kill switch ON. No volts going IN here stops the thing working altogether.

Dark green - this is from the regulator bit of the RR and goes OUT to the rotor. If nothing comes out of this to the rotor, the alternator cant alternate, as the rotor isn't an electromangnet without it. If you plug this IN, then with the ignition and kill switches ON, test the green wire at the rotor. You should have battery voltage or close to it.

Large plug;
Red - this goes to the battery and hopefully charges it when everything else has decided to co-operate.
Yellow 1 - from phase 1 of the alternator stator
Yellow 2 - from phase 2 of the alternator stator
Yellow 3 - from phase 3 of the alternator stator

Note that there will be nothing out of the yellows unless there is power out of the green wire with ignition and kill switch on.

The 'spare' thick black is the negative from the rectifier and needs to be to a good earth for the battery to charge.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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Alan H
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Re: GT380 Alternator Rotor Removal

Post by Alan H »

Good detail jabcb, you posted while I was writing!
Think of how stupid the average person is, then realise that half of them are more stupid than that.
miked914
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Re: GT380 Alternator Rotor Removal

Post by miked914 »

Mine has the 3 yellow from the stator and the 1 red for battery power.

The other plug is 3 wires, Green, Orange and Black. Is the black wire another ground? I don't recall where the other end of it goes to in my wiring loom, will have to check when I get home.

Then I have a separate Black ground coming out as well. I have that line grounded to the Black/White ground wire from the Alternator.
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Re: GT380 Alternator Rotor Removal

Post by Alan H »

It need to be grounded to the frame. Very well as it carries full rectifier charging current.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
miked914
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Re: GT380 Alternator Rotor Removal

Post by miked914 »

Update--With battery power ON, and everything hooked up between the bike and the RR, I checked for voltage on the Orange wire coming out of the RR and the Green Wire on the brushes at the alternator and I've got battery voltage there. Same voltage at the wire, brushes, brush holder and both slip rings (12.6).

Grounds are good all over.

Thoughts on why I'm not charging?
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jabcb
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Re: GT380 Alternator Rotor Removal

Post by jabcb »

You should check the alternator AC voltage with no load.

1) connect the R/R 3-wire connector (orange, green & black wires)
2) do NOT connect the R/R 4-wire connector (red & 3 yellow wires)
3) connect the R/R ground wire

4) run the engine around 2.5k rpm
for the 3 yellow wires from the alternator, check the AC voltage for each combination of two wires
(do not do the test from ground. do the test on the AC scale from one yellow wire to another yellow wire)
Also check the DC voltage at some convenient place on the green wire.

The results will tell us if the rotor & stator are working OK.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
miked914
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Suzuki 2-Strokes: GT380

Re: GT380 Alternator Rotor Removal

Post by miked914 »

thanks jab--I'll give this a go and report back.
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jabcb
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Re: GT380 Alternator Rotor Removal

Post by jabcb »

What exactly do you mean by: "Then I have a separate Black ground coming out as well. I have that line grounded to the Black/White ground wire from the Alternator."
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
miked914
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Suzuki 2-Strokes: GT380

Re: GT380 Alternator Rotor Removal

Post by miked914 »

From my RR I have the 3 yellow wires for the stator, and the red 12V power wire. (1 clip)
2nd clip is the Black, Orange and Green

Then, from the side of the case/body of the RR I have a black wire coming out. I assumed this was for ground.

I have BOTH this "case" black wire and the black wire that is part of the "Green/Orange/Black" clip grounded to the main alternator ground wire. They are both just tied in together then grounded to the B/W wire that goes to the alternator case. Continuity test shows that both wires are grounded
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jabcb
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Re: GT380 Alternator Rotor Removal

Post by jabcb »

The stock setup has the voltage regulator just above the rectifier. The stock rectifier grounds through its attachment bolt.

My plan is to mount the R/R at the same location as the original and run the black ground wire to the rectifier mounting bolt location.
This is easier & leaves the alternator ground wire undisturbed.

“Just tied together” could easily be OK for continuity but then cause you problems down the road because that connection carries 15 to 20 amps.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
miked914
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Re: GT380 Alternator Rotor Removal

Post by miked914 »

jab--do you think my rotor ohm'ing out at 6.5ish is causing my no-charge at this point? I feel like we're knocking out the wiring one by one and I believe its correct at this point.
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